Method, apparatus and computer program product improving real time location systems with multiple location technologies

ABSTRACT

Systems, methods, apparatuses, and computer readable media are disclosed for improving, in some examples, real time location systems with multiple location technologies. In one embodiment, a method is provided including receiving blink data from a location tag associated with a first sensor; receiving proximity data generated based on communications between the first sensor and a second sensor, the proximity data including a sensor identifier; calculating location data associated with the location tag based on the blink data; and determining sensor position calculation data associated with the first sensor based on the proximity data.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.14/298,035, filed Jun. 6, 2014, which claims priority from and thebenefit of U.S. Provisional Patent Application No. 61/831,990, filedJun. 6, 2013, and which is also a continuation in part of U.S. patentapplication Ser. No. 13/942,316, filed Jul. 15, 2013, now U.S. Pat. No.9,002,485, which claims priority from and the benefit of U.S.Provisional Patent Application No. 61/831,990, filed Jun. 6, 2013, thecontents of each are incorporated by reference in their entirety herein.

FIELD

Embodiments discussed herein are related to radio frequency locatingand, more particularly, to systems, methods, apparatus, computerreadable media for improving real time location systems (RTLS) withmultiple location technologies.

BACKGROUND

A number of deficiencies and problems associated with RTLS locating areidentified herein. Through applied effort, ingenuity, and innovation,exemplary solutions to many of these identified problems are embodied bythe present invention, which is described in detail below.

BRIEF SUMMARY

Systems, methods, apparatus, and computer readable media are disclosedfor improving real time location systems (RTLS) with multiple locationtechnologies. In one embodiment, a method of tracking a participantmoving into and outside of a monitored area is provided includingreceiving location data calculated based on blink data transmitted by alocation tag associated with the participant; receiving sensor positioncalculation data calculated based on sensor data transmitted by a sensorassociated with the participant; and determining, by a processor, alocation of the participant based on the location data when theparticipant is in the monitored area and determining, by the processor,a position of the participant based on the sensor position calculationdata when the participant is outside the monitored area.

In some embodiments, the method further includes wherein the locationtag is configured to transmit blink data at a first blink rate whenreceiving a transmission reliability signal within the monitored areaand to transmit blink data at a second blink rate, which is less thanthe first blink rate, when not receiving a transmission reliabilitysignal outside the monitored area.

In some embodiments, the method further includes wherein the processoris configured to determine the location of the participant based on thelocation data and the position of the participant based on the sensorposition calculation data in an order based on a location hierarchy.

In some embodiments, the method further includes receiving to at leastone of the location tag or sensor, a transmission reliability signaltransmitted from one or more exciters positioned proximate the monitoredarea; and determining, by the processor, when the participant is in themonitored area and outside the monitored area based on the transmissionreliability signal.

In some embodiments, the method further includes determining, by theprocessor, the position of the participant based on the sensor positioncalculation data when the participant is in the monitored area.

In some embodiments, the method further includes wherein the processordetermines an over-determined location when the participant is in themonitored area. In some embodiments, the method further includes whereinthe processor does not determine the location of the participant basedon the location data when the participant is outside of the monitoredarea.

In some embodiments, the method further includes wherein the sensorposition calculation data is received through a mesh network. In someembodiments, the method further includes wherein the sensor positioncalculation data is received through a cellular network.

In another embodiment, an apparatus is provided, the apparatuscomprising at least one processor and at least one memory includingcomputer program code, the at least one memory and computer program codeconfigured to, with the processor, cause the apparatus to receivelocation data calculated based on blink data transmitted by a locationtag associated with a participant; receive sensor position calculationdata calculated based on sensor data transmitted by a sensor associatedwith the participant; and determine a location of the participant basedon the location data when the participant is in a monitored area anddetermine a position of the participant based on the sensor positioncalculation data when the participant is outside the monitored area.

In some embodiments, the location tag is configured to transmit blinkdata at a first blink rate when receiving a transmission reliabilitysignal within the monitored area and to transmit blink data at a secondblink rate, which is less than the first blink rate, when not receivinga transmission reliability signal outside the monitored area.

In some embodiments, the apparatus further comprises the at least onememory and computer program code further configured to, with theprocessor, cause the apparatus to determine the location of theparticipant based on the location data and the position of theparticipant based on the sensor position calculation data in an orderbased on a location hierarchy.

In some embodiments, at least one of the location tag or sensor receivesa transmission reliability signal transmitted from one or more exciterspositioned proximate the monitored area; and the apparatus furthercomprises the at least one memory and computer program code furtherconfigured to, with the processor, cause the apparatus to determine whenthe participant is in the monitored area and outside the monitored areabased on the transmission reliability signal.

In some embodiments, the apparatus further comprises the at least onememory and computer program code further configured to, with theprocessor, cause the apparatus to determine the position of theparticipant based on the sensor position calculation data when theparticipant is in the monitored area.

In some embodiments, the apparatus further comprises the at least onememory and computer program code further configured to, with theprocessor, cause the apparatus to determine an over-determined locationwhen the participant is in the monitored area.

In some embodiments, the apparatus does not determine the location ofthe participant based on the location data when the participant isoutside of the monitored area.

In some embodiments, the sensor position calculation data is receivedthrough a mesh network. In some embodiments, the sensor positioncalculation data is received through a cellular network.

In another embodiment, a computer program product comprising anon-transitory computer readable medium having program code portionsstored thereon, the program code portions configured, upon execution toreceive location data calculated based on blink data transmitted by alocation tag associated with a participant; receive sensor positioncalculation data calculated based on sensor data transmitted by a sensorassociated with the participant; and determine a location of theparticipant based on the location data when the participant is in amonitored area and determine a position of the participant based on thesensor position calculation data when the participant is outside themonitored area.

In another embodiment, a location system configured to track aparticipant moving into and outside of a monitored area is provided, thelocation system comprising a location tag configured to transmit blinkdata, wherein the location tag is associated with the participant; asensor configured to transmit sensor data, wherein the sensor isassociated with the participant; a plurality of receivers configured toreceive the blink data and to determine location data based on the blinkdata; and a receiver hub configured to receive the location data andsensor position calculation data calculated based on the sensor data,and determine a location of the participant based on the location datawhen the participant is in the monitored area and determine a positionof the participant based on the sensor position calculation data whenthe participant is outside the monitored area.

In some embodiments, the location system further comprises the locationtag configured to transmit blink data at a first blink rate whenreceiving a transmission reliability signal within the monitored areaand to transmit blink data at a second blink rate, which is less thanthe first blink rate, when not receiving a transmission reliabilitysignal outside the monitored area.

In some embodiments, the location system further comprises the receiverhub further configured to determine the location of the participantbased on the location data and the position of the participant based onthe sensor position calculation data in an order based on a locationhierarchy.

In some embodiments, the location system further comprises receiving toat least one of the location tag or sensor, a transmission reliabilitysignal transmitted from one or more exciters positioned proximate themonitored area; and the receiver hub further configured to determinewhen the participant is in the monitored area and outside the monitoredarea based on the transmission reliability signal.

In some embodiments, the location system further comprises the receiverhub further configured to determine the position of the participantbased on the sensor position calculation data when the participant is inthe monitored area. In some embodiments, the location system furthercomprises the receiver hub further configured to determine anover-determined location when the participant is in the monitored area.

In some embodiments, the location system further comprises the receiverhub further configured to not determine the location of the participantbased on the location data when the participant is outside of themonitored area.

In some embodiments, the location system further comprises wherein thesensor position calculation data is received through a mesh network. Insome embodiments, the location system further comprises wherein thesensor position calculation data is received through a cellular network.

In another embodiment, a location system configured to track aparticipant moving into and outside of a monitored area is provided, thelocation system comprising a location tag associated with theparticipant, wherein the location tag is configured to transmit blinkdata at a first blink rate when the participant is in the monitoredarea, and further configured to transmit blink data at a second blinkrate, which is less than the first blink rate, when the participant isoutside the monitored area. The location system further comprising asensor configured to transmit sensor data, wherein the sensor isassociated with the participant; and a plurality of receivers configuredto receive the blink data transmitted at each of the first blink rateand the second blink rate, and further configured to determine locationdata based on the blink data transmitted at the first blink rate. Thelocation system further comprising a receiver hub configured to receivethe location data determined based on the blink data transmitted at thefirst blink rate, receive sensor position calculation data calculatedbased on the sensor data, and determine a location of the participantbased on the location data when the participant is in the monitored areaand determine a position of the participant based on the sensor positioncalculation data when the participant is outside the monitored area.

In some embodiments, the location system further comprises one or moreexciters positioned about the monitored area, wherein the exciters areconfigured to transmit a transmission reliability signal; and whereinthe location tag is configured to transmit blink data at the first blinkrate upon receiving the transmission reliability signal and is furtherconfigured to transmit blink data at the second blink rate when notreceiving the transmission reliability signal.

In some embodiments, the location system further comprises the receiverhub further configured to determine the location of the participantbased on the location data and the position of the participant based onthe sensor position calculation data in an order based on a locationhierarchy.

In some embodiments, the location system further comprises the receiverhub further configured to determine when the participant is in themonitored area and outside the monitored area based on the transmissionreliability signal.

In some embodiments, the location system further comprises the receiverhub further configured to determine the position of the participantbased on the sensor position calculation data when the participant is inthe monitored area.

In some embodiments, the location system further comprises the receiverhub further configured to determine an over-determined location when theparticipant is in the monitored area. In some embodiments, the locationsystem further comprises the receiver hub further configured to notdetermine the location of the participant based on the location datawhen the participant is outside of the monitored area.

In some embodiments, the location system further comprises wherein thesensor position calculation data is received through a mesh network. Insome embodiments, the location system further comprises wherein thesensor position calculation data is received through a cellular network.

In another embodiment, a method of tracking a participant moving intoand outside of a monitored area is provided including receiving, by alocation tag, a first transmission reliability signal proximate an entryinto the monitored area; transmitting blink data at a first blink rateupon receiving the first transmission reliability signal; receiving, bythe location tag, a second transmission reliability signal proximate anexit from the monitored area; and transmitting blink data at a secondblink rate upon receiving the second transmission reliability signal;wherein the blink data is transmitted to one or more receivers forcalculation of location data based on the blink data transmitted by thelocation tag associated with the participant.

In some embodiments, the method further includes wherein receipt of thefirst transmission reliability signal causes the location tag toincrease the blink rate and receipt of the second transmissionreliability signal causes the location tag to decrease the blink rate.

In some embodiments, the method further includes receiving the firsttransmission reliability signal from a first exciter proximate the entryinto the monitored area and receiving the second transmissionreliability signal from a second exciter proximate the exit from themonitored area.

In some embodiments, the method further includes wherein a processor isconfigured to determine the location of the participant based on thelocation data. In some embodiments, the method further includes whereinthe processor determines an over-determined location when theparticipant is in the monitored area. In some embodiments, the methodfurther includes wherein the processor does not determine the locationof the participant based on the location data when the participant isoutside of the monitored area.

In another embodiment, a location system configured to track aparticipant moving into and outside of a monitored area is provided, thelocation system comprising a location tag associated with theparticipant, wherein the location tag is configured to receive a firsttransmission reliability signal proximate an entry into the monitoredarea; transmit blink data at a first blink rate upon receiving the firsttransmission reliability signal; receive a second transmissionreliability signal proximate an exit from the monitored area; andtransmit blink data at a second blink rate upon receiving the secondtransmission reliability signal. The location system comprising a sensorconfigured to transmit sensor data, wherein the sensor is associatedwith the participant and a plurality of receivers configured to receivethe blink data transmitted at each of the first blink rate and thesecond blink rate, and further configured to determine location databased on the blink data transmitted at the first blink rate. Thelocation system comprising a receiver hub configured to receive thelocation data determined based on the blink data transmitted at thefirst blink rate, receive sensor position calculation data calculatedbased on the sensor data, and determine a location of the participantbased on the location data when the participant is in the monitored areaand determine a position of the participant based on the sensor positioncalculation data when the participant is outside the monitored area.

In some embodiments, the location system further comprises whereinreceipt of the first transmission reliability signal causes the locationtag to increase the blink rate and receipt of the second transmissionreliability signal causes the location tag to decrease the blink rate.

In some embodiments, the location system further comprises two or moreexciters positioned about the monitored area, wherein at least a firstexciter is positioned proximate the entry of the monitored area and isconfigured to transmit the first transmission reliability signal; andwherein at least a second exciter is positioned proximate an exit of themonitored area and is configured to transmit the second transmissionreliability signal.

In some embodiments, the location system further comprises wherein thereceiver hub is further configured to determine the location of theparticipant based on the location data and the position of theparticipant based on the sensor position calculation data in an orderbased on a location hierarchy.

In some embodiments, the location system further comprises the receiverhub further configured to determine when the participant is in themonitored area and outside the monitored area based on the transmissionreliability signal.

In some embodiments, the location system further comprises the receiverhub further configured to determine the position of the participantbased on the sensor position calculation data when the participant is inthe monitored area.

In some embodiments, the location system further comprises the receiverhub further configured to determine an over-determined location when theparticipant is in the monitored area. In some embodiments, the locationsystem further comprises receiver hub further configured to notdetermine the location of the participant based on the location datawhen the participant is outside of the monitored area.

In some embodiments, the location system further comprises wherein thesensor position calculation data is received through a mesh network. Insome embodiments, the location system further comprises wherein thesensor position calculation data is received through a cellular network.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)

Having thus described the invention in general terms, reference will nowbe made to the accompanying drawings, which are not necessarily drawn toscale, and wherein:

FIG. 1 illustrates an exemplary environment equipped with a radiofrequency locating system and sensors for determining a participantlocation or position in accordance with some embodiments of the presentinvention;

FIGS. 2A-E illustrate some exemplary tags and sensor configurations thatmay provide information for participant location or positiondetermination in accordance with some embodiments of the presentinvention;

FIGS. 3A-3F are block diagrams showing the input and output of receiversand sensor receivers in accordance with some embodiments of the presentinvention;

FIG. 4 illustrates an exemplary over-determined locating system that mayutilize multiple location technologies in accordance with some exampleembodiments of the present invention;

FIGS. 5A and 5B illustrate exemplary location technology accuracy andproximity transmission radii in accordance with some of the exampleembodiments of the present invention;

FIG. 6 illustrates an exemplary receiver and transmission reliabilitysignal path in accordance with some example embodiments of the presentinvention;

FIG. 7 illustrates an exemplary over-determined location system withdistinct monitoring areas in accordance with some example embodiments ofthe present invention;

FIG. 8A-C illustrate an exemplary block diagram of processing componentsof the location system in accordance with some example embodiments ofthe present invention; and

FIG. 9 illustrates a flowchart of an exemplary process for determiningtransmissions from a sensor in accordance with some example embodimentsof the present invention;

FIG. 10 illustrates a flowchart of an exemplary process for determiningtransmissions from a mesh node in accordance with some exampleembodiments of the present invention; and

FIG. 11 illustrates a flowchart of an exemplary over-determined locationdetermination process in accordance with some example embodiments of thepresent invention.

DETAILED DESCRIPTION

The present invention now will be described more fully hereinafter withreference to the accompanying drawings, in which some, but not allembodiments of the inventions are shown. Indeed, the invention may beembodied in many different forms and should not be construed as limitedto the embodiments set forth herein; rather, these embodiments areprovided so that this disclosure will satisfy applicable legalrequirements. Like numbers refer to like elements throughout.

Preliminary Definitions

A “tag”, “location tag”, or “locate tag” refers to an ultra-wide band(UWB) transmitter that transmits a signal comprising a burst (e.g., 72pulses at a burst rate of 1 Mb/s), and optionally, a burst having a tagdata packet that may include tag data elements that may include, but arenot limited to, a tag unique identification number (tag UID), otheridentification information, a sequential burst count, stored tag data,or other desired information for object or personnel identification,inventory control, etc. Transmitted tag signals are referred to hereinas “blink data”.

A “sensor” refers to any device that may collect and/or transmit dataother than blink data. Such devices may include, without limitation,position triangulation devices such as global positioning systems (GPS),proximity detectors, accelerometers, magnetometers, time-of-flightsensors, health monitoring sensors (e.g., blood pressure sensors, heartmonitors, respiration sensors, moisture sensors, temperature sensors),light sensors, or the like.

Tags and sensors may be separate units or may be housed in a singlemonitoring unit. In some instances, the tag is configured to be in datacommunication with a sensor. Further, a tag may be configured to be incommunication with a short range low frequency receiver. Tags andsensors may be associated with each other based on proximate mountinglocation at the on a participant or by a tag-sensor correlator, which isdiscussed in detail below. Additionally or alternatively, tags andsensors may be associated in a database, perhaps during a registrationstep, by a receiver hub or receiving processing and distribution system.

A “mesh network” refers to a network of sensors where each sensor in thenetwork is configured to not only transmit its own sensor data but alsoto relay sensor data of other sensors. Mesh networks may transmit sensordata through Wi-Fi protocols such as IEEE 802.11, 802.15 or 802.16,Bluetooth low energy (BLE) protocols, near field communication (NFC)protocols, or the like.

An “origin node” refers to a sensor, associated with a specific tag,which is the origin point of a sensor data transmission in a meshnetwork.

A “mesh node” is a sensor, associated with a specific tag, whichreceives and/or transmits sensor or tag data from an origin node in amesh network. Depending on its status and transmission payload, a sensormay shift between being deemed as an origin node, mesh node or both.

The term “location data” or “locate data” refers to a locationdetermined by the location system based on blink data transmissionsreceived from a location tag by receivers.

The term “position data” refers to data received from sensors that maybe used to determine a sensor position calculation data or position of asensor, which is not based on location tag blink data transmissions.Examples may include triangulation positioning data, such as globalpositioning, telemetry data, or the like.

The term “proximity data” refers to data which includes a sensedidentity within a specified range or radius of the sensor. The sensedidentity may be a fixed location or a mobile identity, such as anotherparticipant.

The term “over-determined location” refers to a calculated location orposition for a tag, sensor, or combination thereof, wherein two or morelocation technologies are used to provide redundancy and/or validationfor the calculated location or position. In some embodiments, theover-determined location may be determined or selected from one or morepositions or locations based on a location hierarchy.

Overview

Some location systems may suffer from degradation or losses of locationdata due to reliance on a single location technology. These losses maybe due to blockages or interference with location tag signals. Forexample, a tag may move out of range of the receiver network, may bemounted to a player at the bottom of a pile in football, in a scrum inrugby, or an individual positioned in close proximity to anotherindividual or other RF limiting body.

Various embodiments of the locate systems discussed herein may increasethe accuracy and prevent degradation or loss of location or positiondata of an object or participant by utilizing a diverse orover-determined locate system. An over-determined locate system mayinclude multiple location technologies including without limitation,ultra wide band (UWB), position triangulation, such as globalpositioning system (GPS), proximity or triangulation positioning, suchas Wi-Fi, BLE, or NFC, or the like.

In one embodiment, the over-determined locate system may use two or moreof the location technologies to provide redundancy and/or validationcross checks of the location data, therefore, allowing the locate systemto support a hierarchy of performance accuracy. For example, a locationhierarchy may be generated with a UWB based locate may be deemed thehighest priority, while proximity to a UWB device may be deemed a secondpriority, and a triangulation based position calculation, such as GPS,may be deemed a third priority. The location system may determine anddisplay and/or store the over-determined location or highestaccuracy/priority location or sensor position calculation dataavailable. Further, the location system may filter or validate locationdata or sensor position calculation data by comparing the variouslocation and sensor position calculation data values to each otherand/or previously received data.

Tag locate technologies that use a line of sight signal between thelocate tag and one or more receivers may produce degraded tag locatedata if the tag loses line of sight communication with the one or morereceivers because of blockage (e.g., a pile up of tagged players infootball). In an instance when the tag cannot be seen one or morereceivers, the associated sensor or origin node may transmit positiondata and/or proximity data to another sensor or mesh node. The sensorsmay transmit position or proximity data through Bluetooth Low Energy(BLE), NFC, Wi-Fi, or the like. The sensor associated with the tag mayhave a specified limited transmission range.

In an example embodiment, proximity or position data may be transmittedto a transceiver using a mesh network routing protocol, wherein theorigin node transmits the proximity data and/or the position data to amesh node. The mesh node then transmits to another mesh node until themessage comprising proximity data and position data reaches a receiver.In some example embodiments, a message count is used to limit the timeor duration of transmission or relaying of the tag message. The messagecount may be a transmission count (e.g., number of time the message hasbeen transmitted from one tag to another tag), a time count, or other ofthe like. In an example embodiment, a directional long range receiverantenna may be used to pull BLE messages directly from a mesh nodewithout relying on a mesh network.

In one example embodiment, the location system includes a transmitter,the transmitter being configured to send a transmission reliabilitysignal to sensors within the monitored area. In an instance in which asensor receives the transmission reliability signal, it may determinethere is not an obstruction or interference to the associated tag, andcause the tag to transmit blink data. In an instance in which thesensor, or in this case origin node does not receive the transmissionreliability signal, the sensor may determine that the tag blink data maybe obstructed and transmit proximity/position data to a mesh node and/ortransmit a distress signal to a mesh node and/or send a signal to thetag to terminate or alter tag blink data. The mesh node may receive andtransmit the proximity or position data to a receiver through a meshnetwork, through a directional antenna backhaul, or the like. In anexample embodiment, the mesh node may only transmit origin node positionor proximity data based on the receipt of a distress signal, which isdescribed in greater detail below.

In an example embodiment, the over-determined location system may usetwo or more locate technologies to filter or validate location data thatmay be blocked, out of range, degraded due to interference, bounced, orthe like. The location system may calculate location (based on tag blinkdata) or position (based on sensor data) based on each of thetechnologies provided and compare them to validate the calculatedlocation or position. In an instance in which a calculated location maybe deemed inaccurate, any associated location data may be deemed asinaccurate and thus dismissed in favor of position data, proximity data,or some combination thereof.

Examples of inaccurate/faulted location data may include tags thatappear to disappear from the network (e.g., no blink data received) fora tag blink cycle or several tag blink cycles. Such non-blinking tagsmay be assumed to be obstructed. Tags may also appear to “pop” or jumpto a distant location due to blink data reflections, or other issues.

Some location technologies are less preferred for particularinstallation environments. For example, UWB based location technologiesmay not be suitable for large or unbounded monitored environments (e.g.,a marathon running course, etc.) due to their reliance on adequatereceiver coverage of the monitored environments. In another example, GPSmay not be suitable for environments requiring precise positiondetermination (e.g., determining precise, i.e., subfoot, movements ofbasketball players, football players, or baseball players).

In one embodiment, multiple location technologies may be used to enablelocation determination in difficult, non-conventional, or eventraditional environments where redundant location determination may bedesirable. The over-determined location system may designate two or moremonitored areas, each having a location hierarchy. For example, in oneembodiment, in race car driving, cars moving around the track area, orfirst monitored area may be monitored by a GPS based positiontechnology, as the highest priority location technology, as precisesubfoot accuracy for car position is not necessary. However, crewmembers moving about the pit area may be monitored by a UWB locationtechnology, as the highest priority location technology, because precisesubfoot accuracy for crew member position may be desired to ensuresafety and to monitor crew member efficiency. In some embodiments, thecombination of two or more location technologies and delineation ofmultiple monitoring areas with associated location hierarchies allowsthe accuracy and coverage range to be specifically designed for the typeof location information desired in each area of the monitored event.

In some embodiments, a tag or sensor may receive a signal indicatingthat it is within or has left the monitored zone of one locationtechnology (e.g., a UWB location technology) and therefore shifttransmission type or frequency. For example, in some embodiments, thesensor may be configured to shift to transmit only position data;transmit only proximity, position, and/or cause the transmission ofblink data; change its blink rate; or the like. In one embodiment, a tagmay receive an indication of the boundary of the monitored area by asignal from an exciter at the transition zone or based on a sensor'sreceipt of a transmission reliability signal. In another exampleembodiment, a sensor may transmit position data and cause thetransmission of the blink data and the locating system may determine anover-determined location, which in various embodiments may comprise thehighest priority location or position that has been calculated based onaccuracy, environment, and information requirements.

The utilization of multiple location technologies may provide a moreaccurate and reliable location system. Further, the use of multiplelocation technologies may facilitate tracking locations and positions atvarying accuracy levels for differing environments and informationalneeds.

Example Real Time Locating System

FIG. 1 illustrates an exemplary locating system 100 useful forcalculating a location by an accumulation of location data or time ofarrivals (TOAs) at a receiver hub 108, whereby the TOAs represent arelative time of flight (TOF) from RTLS tags 102 as recorded at eachreceiver 106 (e.g., UWB reader, etc.). A timing reference clock is used,in some examples, such that at least a subset of the receivers 106 maybe synchronized in frequency, whereby the relative TOA data associatedwith each of the RTLS tags 102 may be registered by a counter associatedwith at least a subset of the receivers 106. In some examples, areference tag 104, preferably a UWB transmitter, positioned at knowncoordinates, is used to determine a phase offset between the countersassociated with at least a subset of the of the receivers 106. The RTLStags 102 and the reference tags 104 reside in an active RTLS field. Thesystems described herein may be referred to as either “multilateration”or “geolocation” systems, terms that refer to the process of locating asignal source by solving an error minimization function of a locationestimate determined by the difference in time of arrival (DTOA) betweenTOA signals received at multiple receivers 106.

In some examples, the system comprising at least the tags 102 and thereceivers 106 is configured to provide two dimensional and/or threedimensional precision localization (e.g., subfoot resolutions), even inthe presence of multipath interference, due in part to the use of shortnanosecond duration pulses whose TOF can be accurately determined usingdetection circuitry, such as in the receivers 106, which can trigger onthe leading edge of a received waveform. In some examples, this shortpulse characteristic allows necessary data to be conveyed by the systemat a higher peak power, but lower average power levels, than a wirelesssystem configured for high data rate communications, yet still operatewithin local regulatory requirements.

In some examples, to provide a preferred performance level whilecomplying with the overlap of regulatory restrictions (e.g. FCC and ETSIregulations), the tags 102 may operate with an instantaneous −3 dBbandwidth of approximately 400 MHz and an average transmission below 187pulses in a 1 msec interval, provided that the packet rate issufficiently low. In such examples, the predicted maximum range of thesystem, operating with a center frequency of 6.55 GHz, is roughly 200meters in instances in which a 12 dBi directional antenna is used at thereceiver, but the projected range will depend, in other examples, uponreceiver antenna gain. Alternatively or additionally, the range of thesystem allows for one or more tags 102 to be detected with one or morereceivers positioned throughout a football stadium used in aprofessional football context. Such a configuration advantageouslysatisfies constraints applied by regulatory bodies related to peak andaverage power densities (e.g., effective isotropic radiated powerdensity (“EIRP”)), while still optimizing system performance related torange and interference. In further examples, tag transmissions with a −3dB bandwidth of approximately 400 MHz yields, in some examples, aninstantaneous pulse width of roughly 2 nanoseconds that enables alocation resolution to better than 30 centimeters.

Referring again to FIG. 1, the object to be located has an attached tag102, preferably a tag having a UWB transmitter, that transmits a burst(e.g., multiple pulses at a 1 Mb/s burst rate, such as 112 bits ofOn-Off keying (OOK) at a rate of 1 Mb/s), and optionally, a burstcomprising an information packet utilizing OOK that may include, but isnot limited to, ID information, a sequential burst count or otherdesired information for object or personnel identification, inventorycontrol, etc. In some examples, the sequential burst count (e.g., apacket sequence number) from each tag 102 may be advantageously providedin order to permit, at a receiver hub 108, correlation of TOAmeasurement data from various receivers 106.

In some examples, the tag 102 may employ UWB waveforms (e.g., low datarate waveforms) to achieve extremely fine resolution because of theirextremely short pulse (i.e., sub-nanosecond to nanosecond, such as a 2nsec (1 nsec up and 1 nsec down)) durations. As such, the informationpacket may be of a short length (e.g. 112 bits of OOK at a rate of 1Mb/sec, in some example embodiments), that advantageously enables ahigher packet rate. If each information packet is unique, a higherpacket rate results in a higher data rate; if each information packet istransmitted repeatedly, the higher packet rate results in a higherpacket repetition rate. In some examples, higher packet repetition rate(e.g., 12 Hz) and/or higher data rates (e.g., 1 Mb/sec, 2 Mb/sec or thelike) for each tag may result in larger datasets for filtering toachieve a more accurate location estimate. Alternatively oradditionally, in some examples, the shorter length of the informationpackets, in conjunction with other packet rate, data rates, and othersystem requirements, may also result in a longer battery life (e.g., 7years battery life at a transmission rate of 1 Hz with a 300 mAh cell,in some present embodiments).

Tag signals may be received at a receiver directly from RTLS tags, ormay be received after being reflected en route. Reflected signals travela longer path from the RTLS tag to the receiver than would a directsignal, and are thus received later than the corresponding directsignal. This delay is known as an echo delay or multipath delay. Ifreflected signals are sufficiently strong enough to be detected by thereceiver, they can corrupt a data transmission through inter-symbolinterference. In some examples, the tag 102 may employ UWB waveforms toachieve extremely fine resolution because of their extremely short pulse(e.g., 2 nsec) durations. Furthermore, signals may comprise shortinformation packets (e.g., 112 bits of OOK) at a somewhat high burstdata rate (1 Mb/sec, in some example embodiments), that advantageouslyenable packet durations to be brief (e.g. 112 microsec) while allowinginter-pulse times (e.g., 998 nsec) sufficiently longer than expectedecho delays, avoiding data corruption.

Reflected signals can be expected to become weaker as delay increasesdue to more reflections and the longer distances traveled. Thus, beyondsome value of inter-pulse time (e.g., 998 nsec), corresponding to somepath length difference (e.g., 299.4 m.), there will be no advantage tofurther increases in inter-pulse time (and, hence lowering of burst datarate) for any given level of transmit power. In this manner,minimization of packet duration allows the battery life of a tag to bemaximized, since its digital circuitry need only be active for a brieftime. It will be understood that different environments can havedifferent expected echo delays, so that different burst data rates and,hence, packet durations, may be appropriate in different situationsdepending on the environment.

Minimization of the packet duration also allows a tag to transmit morepackets in a given time period, although in practice, regulatory averageEIRP limits may often provide an overriding constraint. However, briefpacket duration also reduces the likelihood of packets from multipletags overlapping in time, causing a data collision. Thus, minimal packetduration allows multiple tags to transmit a higher aggregate number ofpackets per second, allowing for the largest number of tags to betracked, or a given number of tags to be tracked at the highest rate.

In one non-limiting example, a data packet length of 112 bits (e.g., OOKencoded), transmitted at a data rate of 1 Mb/sec (1 MHz), may beimplemented with a transmit tag repetition rate of 1 transmission persecond (1 TX/sec). Such an implementation may accommodate a battery lifeof up to seven years, wherein the battery itself may be, for example, acompact, 3-volt coin cell of the series no. BR2335 (Rayovac), with abattery charge rating of 300 mAhr. An alternate implementation may be ageneric compact, 3-volt coin cell, series no. CR2032, with a batterycharge rating of 220 mAhr, whereby the latter generic coin cell, as canbe appreciated, may provide for a shorter battery life.

Alternatively or additionally, some applications may require highertransmit tag repetition rates to track a dynamic environment. In someexamples, the transmit tag repetition rate may be 12 transmissions persecond (12 TX/sec). In such applications, it can be further appreciatedthat the battery life may be shorter.

The high burst data transmission rate (e.g., 1 MHz), coupled with theshort data packet length (e.g., 112 bits) and the relatively lowrepetition rates (e.g., 1 TX/sec), provide for two distinct advantagesin some examples: (1) a greater number of tags may transmitindependently from the field of tags with a lower collision probability,and/or (2) each independent tag transmit power may be increased, withproper consideration given to a battery life constraint, such that atotal energy for a single data packet is less than a regulated averagepower for a given time interval (e.g., a 1 msec time interval for an FCCregulated transmission).

Alternatively or additionally, additional sensor or telemetry data maybe transmitted from the tag to provide the receivers 106 withinformation about the environment and/or operating conditions of thetag. For example, the tag may transmit a temperature to the receivers106. Such information may be valuable, for example, in a systeminvolving perishable goods or other refrigerant requirements. In thisexample embodiment, the temperature may be transmitted by the tag at alower repetition rate than that of the rest of the data packet. Forexample, the temperature may be transmitted from the tag to thereceivers at a rate of one time per minute (e.g., 1 TX/min.), or in someexamples, once every 720 times the data packet is transmitted, wherebythe data packet in this example is transmitted at an example rate of 12TX/sec.

Alternatively or additionally, the tag 102 may be programmed tointermittently transmit data to the receivers 106 in response to asignal from a magnetic command transmitter (not shown). The magneticcommand transmitter may be a portable device, functioning to transmit a125 kHz signal, in some example embodiments, with a range ofapproximately 15 feet or less, to one or more of the tags 102. In someexamples, the tags 102 may be equipped with at least a receiver tuned tothe magnetic command transmitter transmit frequency (e.g., 125 kHz) andfunctional antenna to facilitate reception and decoding of the signaltransmitted by the magnetic command transmitter.

In some examples, one or more other tags, such as a reference tag 104,may be positioned within and/or about a monitored region. In someexamples, the reference tag 104 may be configured to transmit a signalthat is used to measure the relative phase (e.g., the count offree-running counters) of non-resettable counters within the receivers106.

One or more (e.g., preferably four or more) receivers 106 are alsopositioned at predetermined coordinates within and/or around themonitored region. In some examples, the receivers 106 may be connectedin a “daisy chain” fashion to advantageously allow for a large number ofreceivers 106 to be interconnected over a significant monitored regionin order to reduce and simplify cabling, provide power, and/or the like.Each of the receivers 106 includes a receiver for receivingtransmissions, such as UWB transmissions, and preferably, a packetdecoding circuit that extracts a time of arrival (TOA) timing pulsetrain, transmitter ID, packet number, and/or other information that mayhave been encoded in the tag transmission signal (e.g., materialdescription, personnel information, etc.) and is configured to sensesignals transmitted by the tags 102 and one or more reference tags 104.

Each receiver 106 includes a time measuring circuit that measures timesof arrival (TOA) of tag bursts, with respect to its internal counter.The time measuring circuit is phase-locked (e.g., phase differences donot change and therefore respective frequencies are identical) with acommon digital reference clock signal distributed via cable connectionfrom a receiver hub 108 having a central timing reference clockgenerator. The reference clock signal establishes a common timingreference for the receivers 106. Thus, multiple time measuring circuitsof the respective receivers 106 are synchronized in frequency, but notnecessarily in phase. While there typically may be a phase offsetbetween any given pair of receivers in the receivers 106, the phaseoffset is readily determined through use of a reference tag 104.Alternatively or additionally, each receiver may be synchronizedwirelessly via virtual synchronization without a dedicated physicaltiming channel.

In some example embodiments, the receivers 106 are configured todetermine various attributes of the received signal. Since measurementsare determined at each receiver 106, in a digital format, rather thananalog in some examples, signals are transmittable to the receiver hub108. Advantageously, because packet data and measurement results can betransferred at high speeds to a receiver memory, the receivers 106 canreceive and process tag (and corresponding object) locating signals on anearly continuous basis. As such, in some examples, the receiver memoryallows for a high burst rate of tag events (i.e., information packets)to be captured.

Data cables or wireless transmissions may convey measurement data fromthe receivers 106 to the receiver hub 108 (e.g., the data cables mayenable a transfer speed of 2 Mbps). In some examples, measurement datais transferred to the Central Processor/Hub at regular pollingintervals.

As such, the receiver hub 108 determines or otherwise computes taglocation (i.e., object location) by processing TOA measurements relativeto multiple data packets detected by the receivers 106. In some exampleembodiments, the receiver hub 108 may be configured to resolve thecoordinates of a tag using nonlinear optimization techniques.

In some examples, TOA measurements from multiple receivers 106 areprocessed by the receiver hub 108 to determine a location of thetransmit tag 102 by a differential time-of-arrival (DTOA) analysis ofthe multiple TOAs. The DTOA analysis includes a determination of tagtransmit time t₀, whereby a time-of-flight (TOF), measured as the timeelapsed from the estimated tag transmit time t₀ to the respective TOA,represents graphically the radii of spheres centered at respectivereceivers 106. The distance between the surfaces of the respectivespheres to the estimated location coordinates (x₀, y₀, z₀) of thetransmit tag 102 represents the measurement error for each respectiveTOA, and the minimization of the sum of the squares of the TOAmeasurement errors from each receiver participating in the DTOA locationestimate provides for both the location coordinates (x₀, y₀, z₀) of thetransmit tag and of that tag's transmit time t₀.

In some examples, the system described herein may be referred to as an“over-specified” or “over-determined” system. As such, the receiver hub108 may calculate one or more valid (i.e., most correct) locations basedon a set of measurements and/or one or more incorrect (i.e., lesscorrect) locations. For example, a location may be calculated that isimpossible due the laws of physics or may be an outlier when compared toother calculated locations. As such one or more algorithms or heuristicsmay be applied to minimize such error.

The starting point for the minimization may be obtained by first doingan area search on a coarse grid of x, y and z over an area defined bythe user and followed by a localized steepest descent search. Thestarting location for this algorithm is fixed, in some examples, at themean position of all active receivers. No initial area search is needed,and optimization proceeds through the use of a Davidon-Fletcher-Powell(DFP) quasi-Newton algorithm in some examples. In other examples, asteepest descent algorithm may be used.

One such algorithm for error minimization, which may be referred to as atime error minimization algorithm, may be described in Equation 1:

$\begin{matrix}{ɛ = {\sum\limits_{j = 1}^{N}\left\lbrack {\left\lbrack {\left( {x - x_{j}} \right)^{2} + \left( {y - y_{j}} \right)^{2} + \left( {z - z_{j}} \right)^{2}} \right\rbrack^{\frac{1}{2}} - {c\left( {t_{j} - t_{0}} \right)}} \right\rbrack^{2}}} & (1)\end{matrix}$

Where N is the number of receivers, c is the speed of light, (x_(j),y_(j), z_(j)) are the coordinates of the j^(th) receiver, t_(j) is thearrival time at the j^(th) receiver, and t₀ is the tag transmit time.The variable t₀ represents the time of transmission. Since t₀ is notinitially known, the arrival times, t_(j), as well as t₀, are related toa common time base, which in some examples, is derived from the arrivaltimes. As a result, differences between the various arrival times havesignificance for determining location as well as t₀.

The optimization algorithm to minimize the error ε in Equation 1 may bethe Davidon-Fletcher-Powell (DFP) quasi-Newton algorithm, for example.In some examples, the optimization algorithm to minimize the error ε inEquation 1 may be a steepest descent algorithm. In each case, thealgorithms may be seeded with an initial location estimate (x, y, z)that represents the two-dimensional (2D) or three-dimensional (3D) meanof the positions of the receivers 106 that participate in the taglocation determination.

In some examples, the RTLS system comprises a receiver grid, wherebyeach of the receivers 106 in the receiver grid keeps a receiver clockthat is synchronized, with an initially unknown phase offset, to theother receiver clocks. The phase offset between any receivers may bedetermined by use of a reference tag that is positioned at a knowncoordinate position (x_(T), y_(T), z_(T)). The phase offset serves toresolve the constant offset between counters within the variousreceivers 106, as described below.

In further example embodiments, a number N of receivers 106 {R_(j): j=1,. . . , N} are positioned at known coordinates (x_(R) _(j) , y_(R) _(j), z_(R) _(j) ), which are respectively positioned at distances d_(R)^(j) from a reference tag 104, such as given in Equation 2:d _(R) _(j) =√{square root over ((X _(R) _(j) −x _(T))²+(y _(R) _(j) −y_(T))²+(z _(R) _(j) −z _(T))²)}  (2)

Each receiver R_(j) utilizes, for example, a synchronous clock signalderived from a common frequency time base, such as a clock generator.Because the receivers are not synchronously reset, an unknown, butconstant offset O_(j) exists for each receiver's internal free runningcounter. The value of the constant offset O_(j) is measured in terms ofthe number of fine resolution count increments (e.g., a number ofnanoseconds for a one nanosecond resolution system).

The reference tag is used, in some examples, to calibrate the radiofrequency locating system as follows: The reference tag emits a signalburst at an unknown time τ_(R). Upon receiving the signal burst from thereference tag, a count N_(R) _(j) as measured at receiver R_(j) is givenin Equation 3 by:N _(R) _(j) =βτ_(R) +O _(j) +βd _(R) _(j) /c  (3)

Where c is the speed of light and β is the number of fine resolutioncount increments per unit time (e.g., one per nanosecond). Similarly,each object tag T_(i) of each object to be located transmits a signal atan unknown time τ_(i) to produce a count N_(i) _(j) , as given inEquation 4:N _(i) _(j) =βτ_(i) +O _(j) +βd _(i) _(j) /c  (4)

at receiver R_(j) where d_(i) _(j) is the distance between the objecttag T_(i) and the receiver 106 R_(j). Note that τ_(i) is unknown, buthas the same constant value for all receivers. Based on the equalitiesexpressed above for receivers R_(j) and R_(k) and given the referencetag 104 information, phase offsets expressed as differential countvalues are determined as given in Equations 5a-b:

$\begin{matrix}{{{N_{R_{j}} - N_{R_{k}}} = {\left( {O_{j} - O_{k}} \right) + {\beta\left( {\frac{d_{R_{j}}}{c} - \frac{d_{R_{k}}}{c}} \right)}}}{{Or},}} & \left( {5a} \right) \\{\left( {O_{j} - O_{k}} \right) = {{\left( {N_{R_{j}} - N_{R_{k}}} \right) - {\beta\left( {\frac{d_{R_{j}}}{c} - \frac{d_{R_{k}}}{c}} \right)}} = \Delta_{j_{k}}}} & \left( {5b} \right)\end{matrix}$

Where Δ_(jk) is constant as long as d_(R) _(j) −d_(Rk) remains constant,(which means the receivers and reference tag are fixed and there is nomultipath situation) and β is the same for each receiver. Note thatΔ_(j) _(k) is a known quantity, since N_(R) _(j) , N_(R) _(k) , β, d_(R)_(j) /c, and d_(R) _(k) /c are known. That is, the phase offsets betweenreceivers R_(j) and R_(k) may be readily determined based on thereference tag 104 transmissions. Thus, again from the above equations,for a tag 102 (T_(i)) transmission arriving at receivers R_(j) andR_(k), one may deduce the following Equations 6a-b:

$\begin{matrix}{{{N_{i_{j}} - N_{i_{k}}} = {{\left( {O_{j} - O_{k}} \right) + {\beta\left( {\frac{d_{i_{j}}}{c} - \frac{d_{i_{k}}}{c}} \right)}} = {\Delta_{j_{k}} + {\beta\left( {\frac{d_{i_{j}}}{c} - \frac{d_{i_{k}}}{c}} \right)}}}}{{Or},}} & \left( {6a} \right) \\{{d_{i_{j}} - d_{i_{k}}} = {\left( {c/\beta} \right)\left\lbrack {N_{i_{j}} - N_{i_{k}} - \Delta_{j_{k}}} \right\rbrack}} & \left( {6b} \right)\end{matrix}$

Each arrival time, t_(j), can be referenced to a particular receiver(receiver “1”) as given in Equation 7:

$\begin{matrix}{t_{j} = {\frac{1}{\beta}\left( {N_{j} - \Delta_{j\; 1}} \right)}} & (7)\end{matrix}$The minimization, described in Equation 1, may then be performed overvariables (x, y, z, t₀) to reach a solution (x′, y′, z′, t₀′).

In some example embodiments, the location of a tag 102 may then beoutput to a receiver processing and distribution system 110 for furtherprocessing of the location data to advantageously providevisualizations, predictive analytics, statistics and/or the like.

Example Tag/Sensor Positioning and Participant Correlation

FIG. 1 shows a monitored area 100. The monitored area 100 comprises aplurality of positions at one or more time epochs. The plurality ofpositions may be divided into one or more regions, called zones. Eachzone may be described by one or more coordinate systems, such as a localNED (North-East-Down) system, a latitude-longitude system, or even ayard line system as might be used for an American football game. Alocation is a description of a position, or a plurality of positions,within the monitored area. For example, a field marker at theintersection of the south goal line and west out of bounds line at Bankof America Stadium in Charlotte, N.C. could be described as {0,0,0} in alocal NED system, or 35.225336 N 80.85273 W longitude 751 ft. altitudeon a latitude-longitude system, or simply “Panthers Goal Line” in a yardline system. Because different types of locating systems or differentzones within a single locating system may use different coordinatesystems, a Geographical Information System (GIS) or similar monitoredarea database may be used to associate location data. In someembodiments, a Global Coordinate System (such as a latitude-longitudesystem) could describe a plurality of positions encompassing one or moreregions outside the area monitored by the real time location system aswell as one or more zones within the monitored area. In such anembodiment, a participant could be tracked via a Location when withinthe monitored area and via a Coordinate outside the monitored area, ortracked through the use of a Coordinate in either area, as defined bythe Geographical Information System.

Example Tag/Sensor Positioning and Participant Correlation

FIGS. 2a-e illustrate some exemplary tag and sensor configurations thatmay provide information to a location system or over-determined locationsystem in accordance with some embodiments of the present invention. Aparticipant is any person, location or object to which a tag and/orsensor has been attached. FIG. 2a illustrates a participant 202, whichis a football player wearing equipment having attached tags 102 inaccordance with some embodiments. In particular, the depictedparticipant 202 is wearing shoulder pads having tags 102 affixed toopposite sides thereof. This positioning advantageously provides anelevated broadcast position for each tag 102 thereby increasing itscommunication effectiveness. Additional sensors 203 may be attached toequipment worn by participant 202, such as accelerometers,magnetometers, compasses, gyroscopes, time-of-flight sensors, healthmonitoring sensors (e.g., blood pressure sensors, heart monitors,respiration sensors, moisture sensors, temperature sensors), lightsensors, or the like. The additional sensors 204 may be affixed toshoulder pads, the helmet, the shoes, rib pads, elbow pads, the jersey,the pants, a bodysuit undergarment, gloves, arm bands, wristbands, andthe like. In some cases, additional sensors may be fastened to orimplanted under the player's skin, swallowed, or otherwise be carriedinternally in the player's body. Sensors 204 may be configured tocommunicate with receivers (e.g., receivers 106 of FIG. 1) directly orindirectly through tags 102 or other transmitters. For example, in oneembodiment, a sensor 203 may be connected, wired (e.g., perhaps throughwires sewn into a jersey or bodysuit undergarment) or wirelessly, totags 102 to provide sensor data to tags 102, which is then transmittedto the receivers 106. In another embodiment, a plurality of sensors (notshown) may be connected to a dedicated antenna or transmitter, perhapspositioned in the helmet, which may transmit sensor data to one or morereceivers.

In an example embodiment, an array of tags 102 may be attached to theplayer, for example on the head, shoulders, wrists, hips, knees, elbows,feet, or the like, which may be used to determine the location ofvarious portions of the player's body in relation to each other.

FIG. 2b illustrates a participant 206 depicted as a game officialwearing equipment having attached tags 102 and sensors 203 in accordancewith some embodiments. In the depicted embodiment, tags 102 are attachedto the participant's jersey proximate opposite shoulders. Sensors 203are positioned in wristbands worn on the official's wrists as shown.Sensors 203 may be configured to communicate with receivers (e.g.,receivers 106 of FIG. 1) directly or indirectly through tags 102 orother transmitters as discussed above in connection with FIG. 2 a.

As discussed in greater detail below, the positioning of sensors 204(here, accelerometers) proximate the wrists of the participant may allowthe receiver processing and distribution system 110 to determineparticular motions, movements, or activities of the official 206 for usein determining events (e.g., winding of the game clock, first down,touchdown, or the like). The participant 206 may also carry otherequipment, such as penalty flag 208, which may also have a tag 102 (andoptionally one or more sensors) attached to provide additional data tothe receiver processing and distribution system 110. For example, thereceiver processing and distribution system 110 may use tag positiondata from the penalty flag 208 to determine when the official is merelycarrying the penalty flag 208 versus when the official is using thepenalty flag 208 to indicate an event, such as a penalty (e.g., bythrowing the penalty flag 208).

FIG. 2c illustrates an example of a participant 210 depicted as a gameball having tags 102 attached or embedded in accordance with someembodiments. Additionally, sensors 203 may be attached to or embedded inthe ball 210, such as accelerometers, time-of-flight sensors, or thelike. In some embodiments, the sensor 204 may be connected, wired orwirelessly, to tag 102 to provide sensor data to tag 102 which is thentransmitted to the receivers 106. In some embodiments, the sensor 203may transmit sensor data to receivers separately from the tag 102, suchas described above in connection with FIG. 2 a.

FIG. 2d illustrates a monitoring unit 205 including a tag 102 and asensor 203. The tag and sensor may be embodied in a single housing ormonitoring unit 205. The tag and sensor may operate independently or maybe in wired or wireless communication. The sensor 203 may be configuredto transmit signals to the tag 102 to commence, terminate, or change therate of blink data transmissions. The sensor 203 may send signalsconfigured to control the tag blink data transmission by using a lowfrequency transceiver with a range based on the size of the monitoringunit 205.

FIG. 2e illustrates a tag 103 and sensor 203 configuration in which thetag and sensor are separate units. The tag 102 may be associated butoperate independently of the sensor 203, or may be in wired or wirelesscommunication. In an instance in which the tag 102 is in wirelesscommunication with the sensor 203, the sensor may send control signalsto control the tag blink data transmissions as discussed above in FIG.3d . The effective range of the sensor low frequency transmission may be12 inches, 18 inches, 24 inches, 36 inches or any other distance value.The effective range of the low frequency transmission is based on theproximate mounting locations of the tag 102 and sensor 203. In aninstance in which the tag 102 and the sensor 203 are mounted in closeproximity the low frequency transmission may be of a lower range andpower. For example, in an instance in which the tag 102 and sensor 203are mounted 2 inches away from each other on the back of a helmet.Similarly, the range and power of the low frequency transmission may beincreased if the tag 102 and sensor are located further away from eachother. For example, in an instance in which the sensor is mounted to theparticipant's belt at waist level, and the tag is mounted in a shoulderpad.

As will be apparent to one of ordinary skill in the art in view of thisdisclosure, once the tags 102 and sensors 203 of FIGS. 2a-e arepositioned on participants, they may be correlated to such participantsand/or to each other. For example, in some embodiments, unique tag orsensor identifiers (“unique IDs”) may be correlated to a participantprofile (e.g., John Smith—running back, Fred Johnson—line judgeofficial, or ID 027—one of several game balls, etc.) and stored to aremote database accessible to the performance analytics system asdiscussed in greater detail below. Each participant profile may furtherinclude or be correlated with a variety of data including, but notlimited to, biometric data (e.g., height, weight, health data, etc.),role data, team ID, performance statistics, and other data that may beapparent to one of skill in the art in view of the foregoingdescription.

In some embodiments, such participant profile or role data may bepre-defined and stored in association with the unique tag or sensoridentifiers. In other embodiments, the participant profile or role datamay also be “learned” by the system as a result of received tag orsensor data, formation data, play data, event data, and/or the like. Forexample, in some embodiments the system may determine that a tag orsensor is not correlated to a participant profile and may analyze datareceived from the tag and/or sensor to determine possible participantroles, etc., which may be ranked and then selected/confirmed by thesystem or by a user after being displayed by the system. In someembodiments, the system may determine possible participant roles (i.e.,participant role data) based on determined participant position data(e.g., movement patterns, alignment position, etc.).

In some embodiments, as described in greater detail below, theparticipant profile or role data may also be updated by the system(i.e., to produce a data set for the participant that is far more robustthan that established at initial registration) as a result of receivedtag or sensor data, formation data, play data, event data, and/or thelike. In some embodiments, the participant profile and/or role data maybe used in a performance analytics system to weight the actions of theparticipants during analysis to assist in qualifying what is occurring,such as in determining formations, plays, events, etc.

Tag ID and Sensor Data Transmission Architecture

FIGS. 3A, 3B, 3C, 3D, 3E, and 3F show block diagrams of variousdifferent architectures that may be utilized in transmitting signalsfrom one or more tags and sensors to one or more receivers of anover-determined location system in accordance with embodiments of theinvention. In some embodiments, the depicted architectures may be usedin connection with the receiver processing and analytics system 110 ofFIG. 1. More than one of these architectures may be used together in asingle system.

FIG. 3A shows a location tag 102, such as that shown in FIG. 1, whichmay be configured to transmit a tag signal to one or more receivers 106.The one or more receivers 106 may transmit a receiver signal to thereceiver hub 108.

The depicted location tag 102 may generate or store a tag uniqueidentifier (“tag UID”) and/or tag data as shown. The tag data mayinclude useful information such as the installed firmware version, lasttag maintenance date, configuration information, and/or a tag-individualcorrelator. The tag-individual correlator may comprise data thatindicates that a monitored individual (e.g., participant) is associatedwith the location tag 102 (e.g., name, uniform number and team,biometric data, tag position on individual, i.e., right wrist). As willbe apparent to one of skill in the art in view of this disclosure, thetag-individual correlator may be stored to the location tag 102 when thetag is registered or otherwise associated with an individual. Whileshown as a separate field for illustration purposes, one of ordinaryskill in the art may readily appreciate that the tag-individualcorrelator may be part of any tag data or even omitted from the tag.

The tag signal transmitted from location tag 102 to receiver 106 mayinclude “blink data” as it is transmitted at selected intervals. This“blink rate” may be set by the tag designer or the system designer tomeet application requirements. In some embodiments it is consistent forone or all tags; in some embodiments it may be data dependent. Blinkdata includes characteristics of the tag signal that allow the tagsignal to be recognized by the receiver 106 so the location of thelocation tag 102 may be determined by the locating system. Blink datamay also comprise one or more tag data packets. Such tag data packetsmay include any data from the tag 102 that is intended for transmissionsuch as, for example in the depicted embodiment, a tag UID, tag data,and a tag-individual correlator. In the case of TDOA systems, the blinkdata may be or include a specific pattern, code, or trigger that thereceiver 106 (or downstream receiver processing and analytics system)detects to identify that the transmission is from a location tag 102(e.g., a UWB tag).

The depicted receiver 106 receives the tag signal, which includes blinkdata and tag data packets as discussed above. In one embodiment, thereceiver 106 may pass the received tag signal directly to the receivehub/locate engine 108 as part of its receiver signal. In anotherembodiment, the receiver 106 could perform some basic processing on thereceived tag signal. For instance, the receiver could extract blink datafrom the tag signal and transmit the blink data to the receivehub/locate engine 108. The receiver could transmit a time measurement tothe receive hub/locate engine 108 such as a TOA measurement and/or aTDOA measurement. The time measurement could be based on a clock timegenerated or calculated in the receiver, it could be based on a receiveroffset value, it could be based on a system time, and/or it could bebased on the time difference of arrival between the tag signal of thelocation tag 102 and the tag signal of a RF reference tag (e.g., tag 104of FIG. 1). The receiver 106 could additionally or alternativelydetermine a signal measurement from the tag signal (such as a receivedsignal strength indication (RSSI)), a direction of signal, signalpolarity, or signal phase) and transmit the signal measurement to thereceive hub/locate engine 108.

FIG. 3B shows a location tag 202 and sensor 203, such as those worn onan individual's person as shown in FIG. 2, which may be configured totransmit tag signals and sensor signals, respectively, to one or morereceivers 106, 166. The one or more receivers 106, 166 may then transmitreceiver signals to the receiver hub 108. One or more receivers 106, 166may share physical components, such as a housing or antenna.

The depicted location tag 202 may comprise a tag UID and tag data (suchas a tag-individual correlator) and transmit a tag signal comprisingblink data as discussed in connection with FIG. 3A above. The depictedsensor 203 may generate and/or store a sensor UID, additional storedsensor data (e.g. a sensor-individual correlator, sensor type, sensorfirmware version, last maintenance date, the units in whichenvironmental measurements are transmitted, etc.), and environmentalmeasurements. The “additional stored sensor data” of the sensor 203 mayinclude any data that is intended for transmission, including but notlimited to a location tag 202, a reference tag (e.g., 104 of FIG. 1), asensor receiver, a receiver 106, and/or the receiver/hub locate engine108.

The sensor-individual correlator may comprise data that indicates that amonitored individual is associated with the sensor 203 (e.g., name,uniform number and team, biometric data, sensor position on individual,i.e., right wrist). As will be apparent to one of skill in the art inview of this disclosure, the sensor-individual correlator may be storedto the sensor 203 when the sensor is registered or otherwise associatedwith an individual. While shown as a separate field for illustrationpurposes, one of ordinary skill in the art may readily appreciate thatthe sensor-individual correlator may be part of any additional storedsensor data or omitted from the sensor altogether.

Sensors such as sensor 203 that are structured according to embodimentsof the invention may sense or determine one or more environmentalconditions (e.g. temperature, pressure, pulse, heartbeat, rotation,velocity, acceleration, radiation, position, chemical concentration,voltage) and store or transmit “environmental measurements” that areindicative of such conditions. To clarify, the term “environmentalmeasurements” includes measurements concerning the environment proximatethe sensor including, without limitation, ambient information (e.g.,temperature, position, humidity, etc.) and information concerning anindividual's health, fitness, operation, and/or performance.Environmental measurements may be stored or transmitted in either analogor digital form and may be transmitted as individual measurements, as aset of individual measurements, and/or as summary statistics. Forexample, temperature in degrees Celsius may be transmitted as {31}, oras {33, 32, 27, 22, 20, 23, 27, 30, 34, 31}, or as {27.9}. In someembodiments, the sensor-individual correlator could be determined atleast in part from the environmental measurements.

In the embodiment depicted in FIG. 3B, location tag 202 transmits a tagsignal to receiver 106 and sensor 203 transmits a sensor signal tosensor receiver 166. The sensor signal may comprise one or more sensorinformation packets. Such sensor information packets may include anydata or information from the sensor 203 that is intended fortransmission such as, for example in the depicted embodiment, sensorUID, additional stored sensor data, sensor-individual correlator, andenvironmental measurements. A receiver signal from receiver 106 and asensor receiver signal from sensor receiver 166 may be transmitted viawired or wireless communication to receiver hub 108 as shown.

FIG. 3C depicts a sensor 203 communicating through a location tag 202 inaccordance with various embodiments. In one embodiment, the sensor 203may be part of (i.e., reside in the same housing or assembly structure)of the location tag 202. In another embodiment, the sensor 203 may bedistinct from (i.e., not resident in the same housing or assemblystructure) the location tag 202 but configured to communicate wirelesslyor via wired communication with the location tag 202.

In one embodiment, the location tag 202, the sensor 203, or both, maygenerate and/or store a tag-sensor correlator that indicates anassociation between a location tag 202 and a sensor 203 (e.g., tagUID/sensor UID, distance from tag to sensor in a particular stance, setof sensors associated with a set of tags, sensor types associated with atag, etc.). In the depicted embodiment, both the location tag 202 andthe sensor 203 store the tag-sensor correlator.

In the depicted embodiment, sensor 203 transmits a sensor signal tolocation tag 202. The sensor signal may comprise one or more sensorinformation packets as discussed above. The sensor information packetsmay comprise the sensor UID, a sensor-individual correlator, additionalstored sensor data, the tag-sensor correlator, and/or the environmentalmeasurements. The location tag 202 may store some portion of, or all of,the sensor information packets locally and may package the sensorinformation packets into one or more tag data packets for transmissionto receiver 106 as part of a tag signal or simply pass them along aspart of its tag signal.

FIG. 3D illustrates an example communication structure for a referencetag 104 (e.g., reference tag 104 of FIG. 1), a location tag 202, asensor 203, and two receivers 106 in accordance with one embodiment. Thedepicted reference tag 104 is a location tag and thus may include tagdata, a tag UID, and is capable of transmitting tag data packets. Insome embodiments, the reference tag 104 may form part of a sensor andmay thus be capable of transmitting sensor information packets.

The depicted sensor 203 transmits a sensor signal to RF reference tag104. The RF reference tag 104 may store some portion or some or all ofthe sensor information packets locally and may package the sensorinformation packets into one or more tag data packets for transmissionto receiver 106 as part of a tag signal, or simply pass them along aspart of its tag signal.

As was described above in connection with FIG. 1, the receivers 106 ofFIG. 3D are configured to receive tag signals from the location tag 202and the reference tag 104. Each of these tag signals may include blinkdata, which may comprise tag UIDs, tag data packets, and/or sensorinformation packets. The receivers 106 each transmit receiver signalsvia wired or wireless communication to the receiver hub 108 as shown.

FIG. 3E illustrates an example communication structure between alocation tag 202, a plurality of receivers 106, and a variety of sensortypes including, without limitation, a sensor 203, a diagnostic device233, a triangulation positioner 243, a proximity positioner 253, and aproximity label 263 in accordance with various embodiments. In thedepicted embodiment, none of the sensors 203, 233, 243, 253 form part ofa location tag 202 or reference tag 104. However, each may comprise asensor UID and additional stored sensor data. Each of the depictedsensors 203, 233, 243, 253 transmits sensor signals comprising sensorinformation packets.

In the depicted embodiment, receiver 106 is configured to receive a tagsignal from location tag 202 and a sensor signal directly from sensor203. In such embodiments, sensor 203 may be configured to communicate ina communication protocol that is common to location tag 202 as will beapparent to one of ordinary skill in the art in view of this disclosure.

FIG. 3F illustrates an example communication structure between locationtags 202, Origin nodes sensor 203 a, mesh node sensor 203 b, receivers106, transceivers 107 and the receiver hub 108. The a location tag 202,such as that shown in FIG. 1, which may be configured to transmit a tagsignal to one or more receivers 106. The one or more receivers 106 maytransmit a receiver signal to the receiver hub 108. The sensors 203 maybe housed separately from the tag 202 or may be housed in a singlehousing unit. The sensors 203 may be in wired or wireless communicationwith the tags 202 for tag signal control, such as commencing,terminating, or altering tag signal blink rate. The sensors 203 maytransmit sensor data, sensor UID, tag-sensor correlator, or the likedirectly to the sensor receiver 166. In an example embodiment, thesensor receiver 166 may be a long range directional transceiver antennaconfigured to backhaul sensor data directly from a mesh node withoutusing a mesh network.

In an embodiment in which the sensor data is transmitted through a meshnetwork the sensors may be designated as origin node sensors 203 a andmesh node sensors 203 b. A sensor 203 a that originates the sensor datatransmission may be referred to as an origin node 203 a. One or moresensors 203 b that receive and transmit the sensor data from the originnode to the sensor receiver 166 may be referred to as a mesh node 202 b.The origin node 202 a and mesh node 202 b may use Wi-Fi, BLE, or NFC totransmit the sensor data to the next mesh node or sensor receiver 166through a mesh network.

FIGS. 3E/F depicts one type of sensor referred to herein as a “proximityinterrogator”. The proximity interrogator 223 can include circuitryoperative to generate a magnetic, electromagnetic, or other field thatis detectable by a location tag 202. While not shown in FIGS. 3E/F, aproximity interrogator 223 may include a sensor UID and other tag andsensor derived data or information as discussed above.

In some embodiments, the proximity interrogator 223 is operative as aproximity communication device that can trigger a location tag 202(e.g., when the location tag 202 detects the field produced by theproximity interrogator 223) to transmit blink data under an alternateblink pattern or blink rate. The location tag can initiate apreprogrammed (and typically faster) blink rate to allow more locationpoints for tracking an individual. In some embodiments, the location tagmay not transmit a tag signal until triggered by the proximityinterrogator 223. In some embodiments the location tag 202 may betriggered when the location tag 202 moves near (e.g., withincommunication proximity to) a proximity interrogator 223. In someembodiments, the location tag may be triggered when the proximityinterrogator 223 moves near to the location tag 202.

In other embodiments, the location tag 202 may be triggered when abutton is pressed or a switch is activated on the proximity interrogator223 or on the location tag itself. For example, a proximity interrogator223 could be placed at the start line of a racetrack. Every time a carpasses the start line, a car-mounted location tag 202 senses the signalfrom the proximity interrogator and is triggered to transmit a tagsignal indicating that a lap has been completed. As another example, aproximity interrogator 223 could be placed at a Gatorade cooler. Eachtime a player or other participant fills a cup from the cooler aparticipant-mounted location tag 202 senses the signal from theproximity interrogator and is triggered to transmit a tag signalindicating that Gatorade has been consumed. As another example, aproximity interrogator 223 could be placed on a medical cart. Whenparamedics use the medical cart to pick up a participant (e.g., aplayer) and move him/her to the locker room, a participant-mountedlocation tag 202 senses the signal from the proximity interrogator andis triggered to transmit a tag signal indicating that they have beenremoved from the game. As explained, any of these post-triggered tagsignals may differ from pre-triggered tag signals in terms of any aspectof the analog and/or digital attributes of the transmitted tag signal.

FIG. 3E depicts another type of sensor that is generally not worn by anindividual but is referred to herein as a “diagnostic device”. However,like other sensors, diagnostic devices may measure one or moreenvironmental conditions and store corresponding environmentalmeasurements in analog or digital form.

While the depicted diagnostic device 233 is not worn by an individual,it may generate and store a sensor-individual correlator for associationwith environmental measurements taken in connection with a specificindividual. For example, in one embodiment, the diagnostic device 233may be a blood pressure meter that is configured to store asenvironmental measurements blood pressure data for various individuals.Each set of environmental measurements (e.g., blood pressure data) maybe stored and associated with a sensor-individual correlator.

The depicted diagnostic device 233 is configured to transmit a sensorsignal comprising sensor information packets to a sensor receiver 166.The sensor information packets may comprise one or more of the sensorUID, the additional stored data, the environmental measurements, and/orthe sensor-individual correlator as discussed above. The sensor receiver166 may associate some or all of the data from the sensor informationpackets with other stored data in the sensor receiver 166 or with datastored or received from other sensors, diagnostic devices, location tags102, or reference tags. The sensor receiver 166 transmits a sensorreceiver signal to a receiver hub 108.

Another type of sensor shown in FIG. 3E/F is a triangulation positioner243. A “triangulation positioner” is a type of sensor that sensesposition. The depicted triangulation positioner 243 includes a sensorUID, additional stored sensor data, and environmental measurements asdiscussed above.

In some embodiments, a triangulation positioner, such as a globalpositioning system (GPS) receiver receives position data, such as clockdata transmitted by one or more geostationary satellites (a satellite ina known or knowable position) and/or one or more ground basedtransmitters (also in known or knowable positions), compares thereceived clock data, and computes a “position calculation”. The positioncalculation may be included in one or more sensor information packets asenvironmental measurements and transmitted to the receiver hub 108,which may determine the position calculation based on the position data.In an example embodiment the triangulation positioner 243 may comparethe position data clock data and compute a position calculation, whichmay be may be included in one or more sensor information packets asenvironmental measurements and transmitted to the receiver hub 108.Other triangulations positioners may include common timing timedifference of arrival systems, angle of arrival systems, received signalstrength systems, or the like.

In another embodiment, a triangulation positioner comprises one or morecameras or image-analyzers that receive position data, such as emittedor reflected light or heat. The position data may be transmitted to thereceiver hub 108, which may analyze the received position data e.g.,images to determine the position of an individual or sensor. Although atriangulation positioner may transmit data wirelessly, it is not alocation tag because it does not transmit blink data or a tag signalthat can be used by a receiver hub 108 to calculate location. Incontrast, a triangulation positioner senses position data and/orcomputes a position calculation that may then be used as environmentalmeasurements by the receiver hub 108 to determine a position of thesensor.

In an example embodiment the triangulation positioner comprises a RFIDover ISO-2 system or WhereNet™. The ISO-2 system may have active RFIDchips that may be read by a sensor when in proximity to a chip or forcedto transmit at the receipt of a predetermined signal or sensor positiondata. The receiver hub 108 may determine the sensor position calculationbased on the time difference of arrival of the RFID forced transmission.

In one embodiment, a triangulation positioner could be combined with alocation tag or reference tag (not shown). In such embodiments, thetriangulation positioner could compute and transmit its positioncalculation via the location tag to one or more receivers. However, thereceiver hub would calculate tag location based on the blink datareceived as part of the tag signal and not based solely on the positioncalculation. The position calculation would be considered asenvironmental measurements and may be included in associated sensorinformation packets.

As will be apparent to one of ordinary skill in the art, positioncalculations (e.g., GPS receiver position calculations) are not asaccurate as the location calculations (e.g., UWB waveform based locationcalculations) performed by receiver hub/locate engines structured inaccordance with various embodiments of the invention. That is not to saythat position calculations may not be improved using known techniques.For example, a number of influences, including atmospheric conditions,can cause GPS accuracy to vary over time. One way to control this is touse a differential global positioning system (DGPS) comprising one or anetwork of stationary triangulation positioners that are placed in aknown position, and the coordinates of the known position are stored inmemory as additional stored sensor data. These triangulation positionersreceive clock data from geostationary satellites, determine a positioncalculation, and broadcast a difference between the position calculationand the stored coordinates. This DGPS correction signal can be used tocorrect for these influences and significantly reduce location estimateerror.

Another type of sensor shown in FIG. 3E/F is a proximity detector 253. A“proximity detector” is a type of sensor that senses identity within anarea (e.g., a local area) that is small with respect to the monitoredarea 100 of FIG. 1. Many different ways of sensing identity (e.g., aunique ID or other identifier for a sensed object or individual) wouldbe apparent to one of ordinary skill in the art in view of thisdisclosure including, without limitation, reading a linear bar code,reading a two-dimensional bar code, reading a near field communication(NFC) tag, reading a RFID tag such as a passive UHF tag, a passive HFtag, or low frequency tag, an optical character recognition device, abiometric scanner, or a facial recognition system. The identity sensedby the proximity detector 253 and the range or radius associated withthe identity may be referred to as proximity data.

In an example embodiment the proximity detector 253 may be a radiofrequency identification (RFID) chip. The RFID chip may be sensed by anRFID sensor when the RFID sensor is within a predetermined range.

In an example embodiment, the proximity detector 253 may sense aBluetooth Low Energy (BLE) signals identifying sensors. The BLEtransmissions may have a predetermined radius and the transmissions maycomprise the sensor or associated tag UIDs for the proximate sensors.The receiver hub 108 may determine the location of each identifiedproximate sensor based on an associated tag and the predeterminedtransmission radii. The BLE proximity position calculation may bedetermined as the position or area in which the proximity radiiintersect, as depicted in FIG. 5 a.

In an example embodiment, the proximity detector 253 may be a Wi-Fitransceiver. The Wi-Fi transceiver may send and receive Wi-Fi proximityor identity signals to and from sensors within the transmission range.The Wi-Fi transceiver may have a predetermined range or use the RSSI todetermine proximity. In an instance in which the Wi-Fi transceiver has apredetermined broadcast or receiver range, the tag proximity position iscalculated in a manner substantially similar to the BLE transmitterdiscussed above. In an instance in which the Wi-Fi transceiver does nothave a predetermined range, the Wi-Fi RSSI is used to determine theidentified sensors that are closest and furthest from the sensor basedon signal strength. Additionally, an approximation of transmissionradius may be derived from the RSSI and a proximity position calculatedin a manner substantially similar to BLE transmitter above.

In some example embodiments, proximity may be determined based onpredetermined relationships between tags or sensors. In an instance inwhich the tags or sensors move toward or away from each other, thereceiver hub 108 or receiver processing and distribution system 110 maydetermine a change of proximity status associated with the relationship.For example, if a referee has a tag 102 or sensor 203 associated with aportion of his body, such as his shoulder and there is a tag or sensorassociated with a flag kept in a pocket of his uniform, there may be apredetermined relationship between the flag and the shoulder of thereferee. In an instance in which the flag is thrown the proximaterelationship would change and the receiver hub 108 or receiverprocessing and distribution system 110 may update the status of theproximate relationship.

In some embodiments, a proximity detector senses an attribute of anindividual (or an individual's wristband, tag, label, card, badge,clothing, uniform, costume, phone, ticket, etc.). The proximity datae.g., identity sensed by a proximity detector may be stored locally atthe proximity detector 253 as shown and transmitted as proximity datavia one or more sensor information packets to a sensor receiver 166.

In some embodiments, a proximity detector 253 may have a definedposition, which is often stationary, and may be associated with alocation in the monitored area 100 of FIG. 1. For example, a proximitydetector 253 could be located at a finish line of a race track, anentrance gate of a stadium, with a diagnostic device, at a goal line orgoal post of a football field, at a base or home plate of a baseballdiamond, or a similar fixed location. In such embodiments where theproximity detector is stationary, the position coordinates of theproximity detector and a sensor UID could be stored to a monitored areadatabase (not shown) that is accessible by one or more of the receivers106, 166, the receiver hub 108, and/or other components of the receiverprocessing and analytics system 110. In embodiments where the proximitydetector is movable, a position calculation could be determined with atriangulation positioner, or the proximity detector could be combinedwith a location tag and located by the receiver hub 108. While shown asseparate fields for illustration purposes in FIG. 3E/F, identityinformation and position data could comprise part of the additionalstored sensor data, the environmental measurements, or both.

In one embodiment, the proximity detector could be associated with areference tag (e.g., tag 104 of FIG. 1) whose position is recorded inthe monitored area database. In other embodiments, the proximitydetector is movable, such that it may be transported to where it isneeded. For example, a proximity detector 253 could be located on amedical cart, first down marker, a diagnostic device, goal post, orcarried by a paramedic or security guard. In an embodiment where theproximity detector 253 is movable, it would typically be associated witha location tag or triangulation positioner so that location (for alocation tag) or position (for a triangulation positioner) can bedetermined at the time identity is sensed.

In the embodiment where the proximity detector includes a location tag,the receiver hub 108 would locate the associated location tag, and thetag data/sensor data filter would associate the location data for theassociated location tag as the position of the proximity detector, whiledetermining the identity of an associated individual from any receivedsensor information packets. In the alternate embodiment where theproximity detector includes a triangulation positioner, thetriangulation positioner would compute a position calculation that couldbe stored as additional stored sensor data and/or environmentalmeasurements, and transmitted as one or more sensor information packets.In one embodiment, sensor information packets for a proximity detectormay include both sensed identity information and a position calculation.

Another type of sensor shown in FIG. 3E is a proximity label 263. Aproximity label has a fixed position and an identification code (e.g., asensor UID). The proximity label 263 may further comprise additionalstored sensor data as shown. The depicted proximity label 263 isconfigured to be read by proximity detector 253. In some embodiments,proximity detector 253 may be further configured to write information toproximity label 263.

A proximity label 263 may be a sticker, card, tag, passive RFID tag,active RFID tag, NFC tag, ticket, metal plate, electronic display,electronic paper, inked surface, sundial, or otherwise visible ormachine readable identification device as is known in the art. Thecoordinates of the position of the proximity label 263 are stored suchthat they are accessible to the receive hub/locate engine 108. Forexample, in one embodiment, the position coordinates of a proximitylabel 263 could be stored in a field database or monitored area databaseaccessible via a network, or stored locally as additional stored data inthe proximity detector 253.

In some embodiments, a position of the proximity label 263 is encodedinto the proximity label 263 itself. For example, coordinates of aposition of the proximity label 263 could be encoded into a passive RFIDtag that is placed in that position. As another example, the coordinatesof a position of the proximity label 263 could be encoded into a printedbarcode that is placed in that position. As another example, a proximitylabel 263 comprising a NFC tag could be encoded with the location “endzone”, and the NFC tag could be placed at or near an end zone at Bank ofAmerica stadium. In some embodiments, the stored coordinates of theproximity label 263 may be offset from the actual coordinates of theproximity label 263 by a known or determinable amount.

In one embodiment, a proximity label 263 such as an NFC tag may beencoded with a position. When a sensor such as a proximity detectorapproaches the NFC tag it may read the position, then transmit theposition in a sensor information packet to the sensor receiver 166′ andeventually to the receiver hub 108. In another embodiment, a proximitylabel 263 such as a barcode label may be encoded with an identificationcode. When a smartphone with a proximity detector (such as a barcodeimager) and a triangulation positioner (such as a GPS chip, GPSapplication, or similar device) approaches the barcode label it may readthe identification code from the barcode, determine a positioncalculation from received clock data, then transmit the identity and theposition calculation to sensor receiver 166′ and eventually to thereceiver hub 106 as part of one or more sensor information packets.

In the depicted embodiment, triangulation positioner 243 and proximitydetector 253 are each configured to transmit sensor signals carryingsensor information packets to sensor receiver 166′. The depicted sensors243, 253, like any sensor discussed herein, may transmit sensor signalsvia wired or wireless communication protocols. For example, anyproprietary or standard wireless protocol (e.g., 802.11, Zigbee, ISO/IEC802.15.4, ISO/IEC 18000, IrDA, Bluetooth, CDMA, or any other protocol)could be used for the sensor signals. Alternatively or additionally, anystandard or proprietary wired communication protocol (e.g., Ethernet,Parallel, Serial, RS-232, RS-422, USB, Firewire, I²C, etc.) may be used.Similarly, sensor receiver 166′, and any receiver discussed herein, mayuse similar wired and wireless protocols to transmit receiver signals tothe receiver hub/locate engine.

In one embodiment, upon receiving sensor signals from the triangulationpositioner 243 and the proximity detector 253, the sensor receiver 166′may associate some or all of the data from the received sensorinformation packets with other data stored to the sensor receiver 166′,or with data stored or received from other sensors (e.g., sensor 203,audio sensor 105), diagnostic devices 233, location tags 102, or RFreference tags 104. Such associated data is referred to herein as“associated sensor data”. In the depicted embodiment, the sensorreceiver 166′ is configured to transmit some or all of the receivedsensor information packets and any associated sensor data to thereceiver hub 108 at part of a sensor receiver signal.

In one embodiment, a smartphone comprising a proximity detector (such asa barcode imager) and a triangulation positioner (such as a GPS chip)may associate an identification code determined from a barcode with aposition calculation from received clock data as associated sensor dataand transmit a sensor information packet that includes such associatedsensor data to the receiver hub 108. In another embodiment, thesmartphone could transmit a first sensor information packet includingthe identification code and the smartphone's unique identifier toanother sensor receiver, the smartphone could transmit a second sensorinformation packet including the position calculation and thesmartphone's unique identifier to the sensor receiver, and the sensorreceiver could associate the position calculation with theidentification code based on the common smartphone unique identifier andtransmit such associated sensor data to the receiver hub 108. In anotherembodiment, the sensor receiver could determine a first time measurementassociated with the first sensor information packet and a second timemeasurement associated with the second sensor information packet that,in conjunction with the sensor UID, could be used, by the receiver hub108, to associate the first sensor information packet with the secondsensor information packet.

In one embodiment, the receiver hub 108 receives receiver signals fromthe receiver 106 and sensor receiver signals from the sensor receivers166, 166′. In the depicted embodiment, receiver 106 may receive blinkdata from the location tag 102 and transmits to the receiver hub 108some or all of the blink data, perhaps with additional time measurementsor signal measurements. In some embodiments, time measurements or signalmeasurements may be based on a tag signal received from a RF referencetag (e.g., reference tag 104 of FIG. 1). The receiver hub 108 collectsthe blink data, time measurements (e.g., time of arrival, timedifference of arrival, phase), and/or signal measurements (e.g., signalstrength, signal direction, signal polarization, signal phase) from thereceivers 106 and computes location data for the tags 102 as discussedabove in connection with FIG. 1. In some embodiments, the receivers 106may be configured with appropriate RF filters, such as to filter outpotentially interfering signals or reflections proximate the field ofplay or other area to be monitored.

The receiver hub 108 may also access stored data or clock data fromlocal storage and from a network location. The receiver hub 108 usesthis information to determine location data for each location tag. Itmay also associate data derived or extracted from tag signalstransmitted from one or more location tags with information or dataderived or extracted from sensor signals transmitted from one or moresensors.

In addition to the TOA or TDOA systems previously described, otherreal-time location systems (RTLS) such as received signal strengthindication based systems could potentially be implemented by a receiverhub 108. Any RTLS system using location tags, including those describedherein, could require considerable processing by the receiver hub 108 todetermine the location data from the blink data received from the tags.These may require time measurement and/or signal measurement in additionto blink data, which preferably includes a tag UID. In contrast, inother systems, such as global position systems (GPS) systems, locationdata is determined based upon the position calculation transmitted froma GPS transmitter (also referred to as a GPS receiver or GPS tag) whichincludes calculated information about the location where the tag waspositioned (i.e., coordinates determined at the tag via satellite signaltriangulation, etc.) when the position calculation was determined orstored. Thus, GPS information typically refers to additional informationthat is transmitted along with a GPS transmitter ID before thetransmission is received by a sensor receiver.

A GPS host device or back-end server may receive the GPS information andsimply parse the position calculation (as opposed to calculating theposition information at the host device) and the GPS transmitter ID intoa data record. This data record may be used as a GPS positioncalculation, or it could be converted to a different coordinate systemto be used as a GPS position calculation, or it could be processedfurther with DGPS information to be used as a GPS position calculation.

Returning to FIG. 3C, the depicted location tag 202 is used to convey(sometimes called backhaul) sensor information packets to a receiver106. In some embodiments, while not shown, multiple sensors 203 maytransmit sensor signals carrying sensor information packets to locationtag 202. Such received sensor information packets may be associated withblink data that is transmitted to receiver 106.

In one embodiment, the receiver hub 108 may parse sensor informationpackets from received tag data packets and associate such sensorinformation packets with the location tag 202 that transmitted thesensor information packet. Thus, the receiver hub 108 may be able todetermine location data, which may comprise a location and other data(e.g., tag data, tag UID, tag-individual correlator, sensor-individualcorrelator, additional stored sensor data, environmental measurements(e.g., audio data), tag-sensor correlator, identity information,position calculation, etc.) from one or more tags or sensors. Such dataand information may be transmitted to the receiver processing andanalytics system 110.

In some embodiments, once the receiver hub 108 determines a locationestimate of a location tag 102 at the time epoch of the tag signal, thereceiver hub 108 can also associate a location estimate with the tagdata packet included in the blink data of such tag signal. In someembodiments, the location estimate of the tag signal may be used aslocation data for the tag data packet. In some embodiments aGeographical Information System (GIS) may be used by the receivehub/locate engine 108 to refine a location estimate, or to map alocation estimate in one coordinate system to a location estimate in adifferent coordinate system, to provide a location estimate for the tagdata packet.

In one embodiment, the location estimated for the tag data packet may beassociated with any data in the tag data packet, including a tag UID,other tag data, and, if included, one or more sensor informationpackets, including sensor UID, additional stored sensor data, andenvironmental measurements. Since environmental measurements may includea position calculation from a triangulation positioner (e.g., a GPSdevice), the receiver hub 108 could parse the position calculation anduse it to refine a location estimate for the tag data packet.

Preferably, the receiver hub 108 may access an individual database todetermine tag-individual correlators or sensor-individual correlators.Individual data (e.g., an individual profile) may be stored in a server,in tag memory, in sensor memory, or in other storage accessible via anetwork or communication system, including tag data or additional storedsensor data as explained previously.

In some embodiments, by comparing data accessed using asensor-individual correlator, the receiver hub 108 may associate anindividual with a sensor information packet received from a sensor,and/or may associate an individual with such sensor. Because thereceiver hub 108 may associate a sensor position estimate with a sensorinformation packet, the receiver hub 108 may also estimate an individualposition for the associated individual.

In another embodiment, by comparing data accessed using a tag-sensorcorrelator, the receiver hub 108 may associate a sensor with a tag datapacket received from a location tag 102. Because the receiver hub 108may associate a location estimate with a tag data packet, the receiverhub 108 may also create a sensor location estimate for the associatedsensor. By comparing a location estimate for a location tag with asensor location estimate or a sensor position estimate, the receiver hub108 may associate a location tag with a sensor, or may associate a tagdata packet with a sensor information packet. The receiver hub 108 couldalso determine a new or refined tag-sensor correlator based on thisassociation.

In still another embodiment, by comparing a location estimate for alocation tag with an individual location estimate or an individualposition estimate, the receiver hub 108 may associate a location tagwith an individual, or may associate a tag data packet with anindividual. The receiver hub 108 could also determine a new or refinedtag-individual correlator based on this association.

In one embodiment, by comparing a location estimate for a sensor with anindividual location estimate or an individual position estimate, thereceiver hub 108 may associate a sensor with an individual, or mayassociate a sensor information packet with an individual. The receiverhub 108 could also determine a new or refined sensor-individualcorrelator based on this association.

Data derived or extracted from tag signals transmitted from one or morelocation tags is referred to herein as “tag derived data” and shallinclude, without limitation, tag data, tag UID, tag-individualcorrelator, tag-sensor correlator, tag data packets, blink data, timemeasurements (e.g. time of arrival, time difference of arrival, phase),signal measurements (e. g., signal strength, signal direction, signalpolarization, signal phase) and location data (e.g., including taglocation estimates). Tag derived data is not derived by the locationtag, but rather, is derived from information transmitted by the locationtag. Information or data derived or extracted from sensor signalstransmitted from one or more sensors is referred to herein as “sensorderived data” and shall include, without limitation, sensor UID,additional stored sensor data, sensor-individual correlator,environmental measurements, sensor information packets, positioncalculations (including sensor position estimates), positioninformation, identity information, tag-sensor correlator, and associatedsensor data. Information or data derived or extracted from audio sensorsignals transmitted by one or more audio sensors is referred to hereinas “audio data” and shall include without limitation, audio sensor UID,additional stored audio sensor data, audio sensor-individual correlator,audio sensor information packets, tag-audio sensor correlator, andassociated audio sensor data. Data derived or extracted from storedindividual data is referred to herein as “individual profileinformation”, “participant profile information”, or simply “profileinformation” and shall include, without limitation tag-individualcorrelator, sensor-individual correlator, identity information, name,uniform number and team, biometric data, tag position on individual. Invarious embodiments, the receiver hub 108 may transmit tag derived data,sensor derived data, individual profile information, variouscombinations thereof, and/or any information from the GIS, the fielddatabase, the monitored area database, and the individual database tothe receiver processing and analytics system 110.

Exemplary Over-Determined Location System with Multiple LocationTechnologies

FIG. 4 illustrates a diagram of an over determined location system withmultiple location technologies. The location system may includeparticipants 402 a-e, tags 102, sensors 203, monitoring unit 510,receivers 106, transceivers 107 and 107 a, a receiver hub 108, areceiver processor and distribution system 110, and exciters 112.Participants 402 a-e may carry a tag 102 and a sensor 203 or amonitoring unit 510, as depicted in the participant 402 breakouts. Thefollowing descriptions of tags 102 and sensors 203 may include the tagsand sensors housed within the monitoring unit 510, or separatelymounted. Tags 102 and sensors 203 may be referred to by their associatedparticipant designator. For example participant 402 a may carry tag 102a and sensor 102 a. Each tag 102 a-e may transmit blink data asdescribed above in FIG. 1. Sensors 203 a-e may transmit proximity and/orposition data or receive and transmit proximity and/or position datafrom other sensors as described in FIG. 3. The transceiver 107 mayfunction as a sensor receiver, such as sensor receiver 166 of FIG. 3E/F.

Proximity data may include BLE, NFC, Wi-Fi or other communicationtransmissions comprising the tag UID or sensor UID for each sensor thatis within range. The proximity data may be a proximity detectoridentification of proximate sensors, such as sensor or tag UIDs having apredetermined range, or proximity radii, such as Wi-Fi RSSI. Positiondata may include without limitation triangulation position data, such asGPS or ISO-2, telemetry data, or other data that may be used todetermine the sensor position. The sensors 203 a-e may transmit theproximity data or position data by NFC, Wi-Fi, BLE, or the like.

In an instance in which a sensor is the origin point for transmission ofproximity or position data, the sensor may be referred to as an originnode. In an instance in which the sensor receives and/or transmits theproximity or position data of an origin node, the sensor may be referredto as a mesh node. A sensor may dynamically shift between origin node,mesh node or both based on transmitting the sensor data from anothersensor, its own sensor data or both as described below.

An origin node 203 a may transmit proximity data or position data tomesh nodes 203 b, 203 c, or 203 d. Mesh nodes 203 b, 203 c, 203 d may beconfigured to relay the proximity data or position data to a transceiver107 using a mesh network protocol. In an example embodiment sensor 203 bmay be an origin node and a mesh node when transmitting proximity orposition data from sensor 203 a and transmitting its own proximity orposition data. Similarly, sensor 203 b may be an origin node whentransmitting proximity or position data to mesh nodes 203 c.

In an example embodiment, a directional long range transceiver antenna107 a may pull the proximity or position data from the origin node 203 aor mesh node 203 b directly without using a mesh network. In an exampleembodiment, the mesh network may be utilized to transmit position orproximity data out of an area of interference such as physicalinterference of a player pile up, and backhauled through the directionallong range transceiver antenna 107 a.

In an example embodiment, the origin node 203 a and subsequent meshnodes 203 b-e append their associated tag UID or sensor UID to thetransmission of sensor proximity or position data. The tag/sensor UIDsmay be used by the mesh nodes 203 b-e to determine a transmission countas described below. Additionally, the receiver hub 108 or receiverprocessing and distribution system 110 may use the tag/sensor UIDs forsystem analytics or diagnostics. For example the receiver hub 108 orreceiver processing and distribution system 110 may determine the routea proximity or position data message took through the mesh network.

In an example embodiment, the duration of relay transmissions of theproximity data or position data message through a mesh network may belimited by a message count. The limitation of the message transmissionduration prevents a message from cycling throughout the mesh networkindefinitely, or continuing transmission after the message has beenreceived by transceiver 107. A message count may be a number oftransmissions from sensor to sensor (e.g., transmission count) suchthree transmissions, four transmissions, five transmissions, or anyother number of transmissions. The message count may be a time countsuch as 3 seconds, 2 seconds, 1 second, ½ second, or any other timevalue.

In an instance in which the message count does not satisfy apredetermined threshold (e.g. 4 transmissions or 3 seconds), the meshnode 203 b-e may transmit the received origin node 203 a proximity orposition data. In an instance in which the message count satisfies apredetermined threshold (e.g., 4 transmissions or 3 seconds), the meshnode 203 b-e may not transmit the received origin node 203 a proximityor position data.

For example, the origin node 203 a may transmit proximity or positiondata to a mesh node 203 b, and mesh nodes 203 b may transmit to meshnodes 203 c-d. In an instance in which the message count threshold isfour transmissions, mesh node 203 d is the last transmission of themessage. The message may be received by a transceiver 107 which sendsthe message to the receiver hub 108 for processing, or be received byanother mesh node 203 e. The message count threshold is satisfied in aninstance in which the mesh node 203 e receives the message and the meshnode disregards the message, terminating the message route.

In another example, the origin node 203 a may transmit proximity orposition data to a mesh node 203 b with a time notation, and mesh nodes203 b may transmit to mesh nodes 203 c-d. In an instance in which themessage count threshold is 3 seconds, mesh nodes 203 b-d each verify thetime notation is less than 3 seconds. Where the transmission to meshnode 203 d occurs prior to 3 seconds and subsequent transmission wouldexceed 3 seconds, the transmission from 203 d is the last transmissionof the message. The message may be received by a transceiver 107 whichsends the message to the receiver hub 108 for processing, or be receivedby another mesh node 203 e. The message count threshold of 3 seconds issatisfied in an instance in which the mesh node 203 e receives themessage and the mesh node disregards the message, terminating themessage route.

In an example embodiment, the receiver hub 108 or receiver processingand distribution system 110 may determine the best route for a proximityor position data message. The receiver hub 108 or receiver processingand distribution system 110 may determine that the blink data has notbeen received for a specified tag. The receiver hub 108 or receiverprocessing and distribution system 110 may use the last known locationof the tag 102 a and/or the participants' 402 a position calculationsand the locations or position calculations for other participants 402b-e in the monitored area to determine the best route for the message toreach a transceiver 107 (e.g., smallest number of transmissions). Thereceiver hub 108 or the receiver processing and distribution system 110may cause the transceiver 107 to transmit the message route to themonitored area. The sensors 203 may be configured with a transceiver toreceive message route or other control signals from the receiver hub 108or processing and distribution system 110. In an instance in which amesh node 203 b-d receives a proximity or position data message, themesh node may determine if the mesh node is designated in the messageroute. If the sensor is designated the mesh node 203 b-e may transmitthe proximity and position data message along with its own data. In aninstance in which the mesh node 203 b-e is not designate the mesh nodedismisses the received proximity or position data.

In an example embodiment, the monitored area 100 may have transmitters,such as exciters 112, placed at the boundary of the monitored area. Theexciters 112 may transmit a short range LF signal or a transmissionreliability signal. The exciters 112 may transmit the transmissionreliability signal repeatedly, such as continuously or nearcontinuously. The tags 102 a-e and/or sensors may include a short rangeLF receiver for setting tag blink rate. The exciters 112 may be a seriesof ground mounted exciters, the tags or sensors may receive thetransmission reliability signal as the participant passed over theexciter. In an example embodiment, the exciters 112 may be mounted in aring in which the participant must pass through to enter or exit amonitored area.

The transmission reliability signal from the exciters 112 may bereceived by the tag 103 receiver and change the state of blink datatransmission. Additionally or alternatively, the transmissionreliability signal may be received by a sensor 203, the sensor may inturn transmit a signal configured to cause the tag 102 to change blinkdata transmission state. The transmission reliability signal may be usedto transition the tag blink data transmissions based on being within oroutside of the monitored area. For example, tags 102 a-e may transmitblink data when they are within the monitored area or to ceasetransmitted blink data when they leave the monitored area as indicatedby crossing through the transmission reliability signal of the exciters112. Additionally, exciters 112 may be used to signal to sensors 203 totransmit proximity data or position data when within the monitored areaor cease transmitting proximity or position data when not within themonitored area in a manner similar to tags as described.

In an example embodiment, tags alter their blink rate based on thereceipt of the transmission reliability signal. For example the tag mayblink at 56 Hz when within the monitored area and 1 Hz when outside ofthe monitored area. In other embodiments, the tag 102 and associatedsensor 203 may transmit via one or multiple location methods within amonitored area and transmit on a different or single location methodwhen outside of the monitored area. For example, transmitting blink datafrom the tag 102 and proximity data from the sensor 203 within themonitored area and transmitting only position data outside of themonitored area. Tags 102 terminating transmission or high blink ratetransmission when outside of the monitored area may increase batterylife of the tag 102 and reduce processor load on the receiver hub 108.

In another example embodiment, the monitored area 100 may have one ormore first exciters 112 placed at the boundary of the monitored areaproximate one or more entry points to the monitored area and one or moresecond exciters 112 placed at the boundary of the monitored areaproximate one or more exit points from the monitored area. The firstexciters 112 may transmit a first short range LF signal or a firsttransmission reliability signal. The second exciters 112 may transmit asecond short range LF signal or a second transmission reliabilitysignal. The exciters 112 may transmit the transmission reliabilitysignal repeatedly, such as continuously or near continuously. The tags102 a-e and/or sensors may include a short range LF receiver forreceiving transmission reliability signals and using such signals forsetting tag blink rate. The tags 102 may increase their blink rate basedon the receipt of the first transmission reliability signal upon entryto the monitored area. The tags 102 may decrease their blink rate basedon the receipt of the second transmission reliability signal upon exitfrom the monitored area.

In an example embodiment, a transmitter 107 may transmit a transmissionreliability signal to the monitored area. The transmission reliabilitysignal may be received by a sensor 203 a. In an instance when the 203 areceives the transmission reliability signal it may transmit proximitydata and position data or not transmit if configured to transmit onlywhen the tag 102 location may not be calculated. If the sensor 203 afails to receive the transmission reliability signal the sensor mayassume that the tag blink data is obstructed, for example, by a pile upof players in football. An illustration of an example obstruction isdepicted in FIG. 6, the tag 102 a and associated sensor 203 (not shown)does not have a direct line of sight to the receiver 106 due toparticipants 402 b blocking the tag signal or any other physicalobstruction to the tag signal. In an instance in which the sensor 203 adoes not receive the transmission reliability signal, the sensor maytransmit proximity data and/or position data to mesh nodes 203 b. Meshnode 203 b may transmit its own blink data, proximity data, and/orposition data and origin node 203 a position data and/or proximity data.Additionally, sensor 203, may transmit a signal to the tag 102configured to cause the termination of blink data transmissions or lowerblink rate. When the transmission reliability signal is received at thesensor 203 a, the sensor may transmit a signal configured to cause thetag 102 a to recommence blink data transmissions or increase blink rate.

In an example embodiment, if sensor 203 a fails to receive thetransmission reliability signal, it may also transmit a distress signal.The distress signal may be indicative of a tag or sensor signalblockage. The distress signal may be received by a mesh node sensor 203b. In an instance in which a mesh node 203 b receives the distresssignal and proximity or position data, mesh node may transmit its ownproximity data, and/or position data and origin node 203 a position dataand/or proximity data. In an instance in which mesh node 203 b does notreceive a distress signal, it may transmit only its own proximity dataand/or position data and not transmit origin node 203 a's position dataor proximity data, having determined that the origin node is notobstructed.

The receiver hub 108 may generate a location hierarchy by assigning apriority value to each of the location and position methods for whichthe location system is equipped. For example, UWB location may beassigned a priority value of 1; proximity position calculation based ona UWB location may have a priority value of 2; GPS position calculationbackhauled over Wi-Fi or ISO-2 may have a priority value of 3; ISO-2,Wi-Fi RSSI, and proximity position calculation based on GPS position mayhave a priority value of 4; where 1 represents the highest priorityvalue and 4 the lowest priority value.

The blink data, proximity data, and position data may be received at thereceiver hub 108 or receiver processing and distribution system 110 fromthe receivers 106 and/or transceivers 107. The receiver hub 108 or thereceiver processing and distribution system 110 may calculate taglocations based on the blink data as discussed in FIG. 1. The receiverhub may determine sensor proximity data and/or sensor position data. Thereceiver hub 108 or receiver processing and distribution system 110 mayuse the location data, proximity data, and/or position data to determinea origin node position calculation based on available location andsensor position calculation data from mesh nodes.

In an embodiment, the receiver hub 108 or the receiver procession anddistribution system 110 may receive proximity data for a sensor 203 a.The proximity data may include data, such as tag or sensor UIDs,identifying one or more mesh nodes 203 b in proximity to the specifiedorigin node 203 a. The origin node 203 a may have a predetermined rangefor transmission of the proximity data, limiting the receipt of theproximity data to a specified radius. For example, the range may be 10ft, 4 ft, 2 ft, or any other radial distance value. The receiver hub 108or receiver processing and distribution system 110 may calculate meshnode 102 b location based on blink data and a proximity radius for eachmesh node to determine a position calculation for the origin node 102 aas illustrated in FIG. 5 a.

In an example embodiment, the receiver hub 108 or receiver processingand distribution system 110 may receive position data for an origin node203 a. The position data may include telemetry data, such as Wi-Fi, or atriangulated position, such as GPS. The receiver hub 108 or the receiverprocessing and distribution system 110 may determine a positioncalculation based on the available telemetry data or triangulationposition data as discussed in FIG. 3E/F.

The receiver hub 108 or the receiver processing and distribution system110 may validate calculated tag locations using the determine positiondata and/or previous location/position data. The validation may reducethe occurrences of bounced blink data causing inaccurate locates orother anomalies in the tag location determination. The receiver hub 108or the receiver processing and distribution system 110 may compare thecurrent location data to the previously location data. Previouslylocation data may include the last 2, 5, 10, 20 or another number oflocation data that were calculated before location data that is beingvalidated. In an instance in which the change in location data satisfiesa predetermined threshold such as 2 ft, 5 ft, 20 ft, 30 ft, 100 ft, orany other distance value, the receiver hub 108 or the receiverprocessing and distribution system 110 may determine that the tag 102could not travel the determined distance between blinks and dismiss thelocation data. For example, in an instance in which the location datachanges by 35 ft and the predetermined threshold is 20 ft, the receiverhub 108 or receiver processing and distribution system 110 may dismissthe location data.

In an example embodiment, the receiver hub 108 may compare the locationdata of a participant 402 a to the location data of participants 402 bthat have received the origin node 203 a proximity data. The receiverhub 108 or the receiver processing and distribution system 110 maydetermine that the tag 102 a location data is within the mesh nodes 203b proximity radius and is therefore valid, as shown in FIG. 5a . Thereceiver hub 108 or receiver processing and distribution system maydetermine that the tag 102 a location data is outside of the mesh node102 b proximity radius and therefore the location data is invalid anddismiss the location data as unavailable.

In an example embodiment, the receiver hub 108 or receiver processingand distribution system 110 may compare the tag 102 location data to thedetermined positions based on the position data received from the sensor203 a. The receiver hub 108 or receiver processing and distributionsystem 110 may determine that the location data is within the positioncalculation accuracy radius or radii, as shown in FIG. 5b , andtherefore the location data is valid. The receiver hub 108 or receiverprocessing and distribution system 110 may determine that the locationdata is outside of the determined sensor position calculation accuracyand dismiss the location data as unavailable.

The receiver hub 108 or the receiver processing and distribution system110 may determine a message route based on the last location data of theparticipant 402 and the location data and position calculations of otherparticipants. The receiver hub 108 or the receiver processing anddistribution system 110 may determine the shortest route, e.g. thesmallest number of transmissions through a mesh network to thetransceiver 107 and designate mesh nodes 203 b-e. The receiver hub 108or receiver processing and distribution system 110 may cause thetransceiver 107 to transmit the message route to the monitored area forreceipt by sensors 203 a-e.

The receiver hub 108 or the processing and distribution system 110 maydetermine the highest priority location or position data available, orover-determined location. The receiver hub 108 or receiver processingand distribution system 110 may determine which location methods areavailable (e.g. providing an accurate or valid location or position).The receiver hub 108 or receiver processing and distribution system 110may select the available location or sensor position calculation datawhich has the highest assigned priority value, in a location hierarchy.For example, if UWB location-priority 1 and GPS positioncalculation-priority 2 are available the receiver hub 108 or receiverprocessing and distribution system 110 may select the UWB location. Inan instance in which the receiver hub 108 or receiver processing anddistribution system 110 determines that UWB proximity positioncalculation-priority 2 and Wi-Fi-priority 3 are available, UWB proximityposition calculation may be selected. In an instance in which two ormore location methods are available and have the same priority value thedetermined position may be an average of the selected locations orpositions.

The receiver hub 108 or receiver processing and distribution system maycause the display of the selected location or sensor positioncalculation data on a graphic user interface (GUI). In an exampleembodiment the selected location or sensor position calculation data isdisplayed on the GUI overlaid with the other available location orposition data. Additionally, the receiver hub 108 or receiver processingand distribution system may cause all or at least the selected locationand sensor position calculation data to be stored in a memory for lateranalysis or display.

Example Over-Determined Location System with Distinct Monitoring Areas

FIG. 7 illustrates a diagram of an over-determined location systemutilizing multiple location technologies. The location system includingtagged participants 402/402 a, receivers 106, transceivers 107, areceiver hub 108, a receiver processing and distribution system 110,exciters 112, a Wi-Fi receiver 113, and a cellular (3G) receiver 114. Inan event location such as a race track, a cross county field or abicycle course, a single location technology may not be suitable todeliver accurate location over the range of the event terrain or area. Alocation system may utilize multiple location technologies to deliverthe type of information required at different areas of the event. Forexample, on a race track a location may be desired, but a subfootlocation may be unnecessary. However within the same event in the pitarea high accuracy location of tools, personnel, cars, or the like maybe desired for safety and analytics. In another example, UWB locationsmay be highly desirable at the finish line of events as a method ofdetermining a winner of a race, but subfoot accuracy may not benecessary for the remainder of the event.

The receiver hub 108 or receiver processing and distribution system 110may generate a location hierarchy for each monitored areas of the event.For example, in the first monitored area, such as the pit, transitionpoint or pit the receiver hub 108 or receiver processing anddistribution system 110 may establish a location hierarchy by assigninga priority of 1 to UWB location and a priority of 2 to positioncalculations, such as GPS. In a second monitored area, such as the racetrack, race course, or the like, the receiver hub 108 or receiverprocessing and distribution system may establish a location hierarchy byassigning a priority of 1 to position calculations, such as GPS, and apriority of 2 to UWB location data, which may or may not be available.The receiver hub 108 or receiver procession and distribution system 110may determine an over-determined location based on the location data,sensor position calculation data and the location hierarchy of the firstor second monitored area.

Continuing the example, participants 402/402 a may carry tags 102,sensors 203 or a monitoring unit 510 as discussed in FIGS. 2 and 4. Inan instance in which participant 402 is outside of the UWB monitoredarea of the event, here the pit, the tag may utilize DGPS or othertriangulation positioning and transmit the position data to the receiverhub through a Wi-Fi 113 or 3G receiver 114. When a participant 402 aenters the monitored area, such as the pit of a race track, UWB blinkdata may be received by receivers 106 and a location data calculated asdiscussed above in FIG. 1. The pit crew can use the high accuracylocation data in the pit area to for analytics such as, determiningoptimum pit crew deployment to decease pit stop time and determiningcrew member locations to prevent injury.

The tag 102 a may receive a transmission reliability signal from anexciter 112. The tag 102 a may commence transmitting when it receivesthe transmission reliability signal and may cease transmission when itexits the transmission reliability signal area as discussed in FIG. 4.In an example embodiment, the sensor 203 a may receive a transmissionreliability signal from transmitter 107 or exciters 112. The sensor 203a may transmit proximity data or position data, based on receiving ornot receiving the transmission reliability signal as discussed above inFIG. 4. Further, the sensor may transmit a signal configured to causethe tag 102 a to transition the tag blink rate based on the receipt ofthe transmission reliability signal as discussed above in FIG. 4. Insome example embodiments, the pit may be a first zone of a monitoredarea and the event area outside of the first zone of the monitored area,e.g. the race track, may be a second zone of the monitored area.

Example Processing Module

FIG. 8a shows a block diagram of components that may be included in aprocessing module 800. Processing module 800 may comprise one or moreprocessors, such as processor 802, one or more memories, such as memory804, and communication circuitry 806. Processor 802 can be, for example,a microprocessor that is configured to execute software instructionsand/or other types of code portions for carrying out defined steps, someof which are discussed herein. Processor 802 may communicate internallyusing data bus, for example, which may be used to convey data, includingprogram instructions, between processor 802 and memory 804.

Memory 804 may include one or more non-transitory storage media such as,for example, volatile and/or non-volatile memory that may be eitherfixed or removable. Memory 804 may be configured to store information,data, applications, instructions or the like for enabling processingmodule 800 to carry out various functions in accordance with exampleembodiments of the present invention. For example, the memory 804 couldbe configured to buffer input data for processing by processor 802.Additionally or alternatively, the memory 804 could be configured tostore instructions for execution by processor 802. Memory 804 can beconsidered primary memory and be included in, for example, RAM or otherforms of volatile storage which retain its contents only duringoperation, and/or memory 804 may be included in non-volatile storage,such as ROM, EPROM, EEPROM, FLASH, or other types of storage that retainthe memory contents independent of the power state of the processingmodule 800. Memory 804 could also be included in a secondary storagedevice, such as external disk storage, that stores large amounts ofdata. In some embodiments, the disk storage may communicate withprocessor 802 using an input/output component via a data bus or otherrouting component. The secondary memory may include a hard disk, compactdisk, DVD, memory card, or any other type of mass storage type known tothose skilled in the art.

In some embodiments, processor 802 may be configured to communicate withexternal communication networks and devices using communicationscircuitry 806, and may use a variety of interfaces such as datacommunication oriented protocols, including X.25, ISDN, DSL, amongothers. Communications circuitry 806 may also incorporate a modem forinterfacing and communicating with a standard telephone line, anEthernet interface, cable system, and/or any other type ofcommunications system. Additionally, processor 802 may communicate via awireless interface that is operatively connected to communicationscircuitry 806 for communicating wirelessly with other devices, using forexample, one of the IEEE 802.11 protocols, 802.15 protocol (includingBluetooth, Zigbee, and others), a cellular protocol (Advanced MobilePhone Service or “AMPS”), Personal Communication Services (PCS), or astandard 3G wireless telecommunications protocol, such as CDMA20001×EV-DO, GPRS, W-CDMA, LTE, and/or any other protocol.

Example Sensor

FIG. 8b shows a block diagram of components that may be included in asensor 820. The sensor 820 may include a processing module 800 and atransmission module 822. The sensor 820 may include a transmissionmodule 822 which may, in turn be in communication with the processor802, or the processing module 800. The transmission module 822 may beconfigured to cause the processor 802 to determine receipt of atransmission reliability signal; and cause transmission of sensorproximity data or position data based on the determination of thetransmission reliability signal. In an embodiment, the transmissionmodule 822 may be configured to cause the processor 802 to cause thetransmission of a distress signal or blink data based on thedetermination of the receipt of the transmission reliability signal. Inan example embodiment, the transmission module 822 may be configured tocause the processor 802 to receive proximity data and/or position datafrom an origin node and transmit a signal configured to cause thetransmission of blink data, sensor proximity data or sensor positiondata, and origin node position and/or proximity data. The transmissionmodule 822 may be further configured to cause the processor 802 toreceive a distress signal from an origin node, and cause thetransmission of the origin node proximity and/or position data based onthe receipt of the distress signal. The transmission module 822 may alsobe configured to cause the processor 802 to determine if a message counthas satisfied a predetermined threshold and the transmission of originnode proximity and/or position data is based on the message countdetermination.

Example Apparatus

FIG. 8c shows a block diagram of components that may be included in anapparatus 830 such as the receiver hub 108 or receiver processing anddistribution system 110 of FIG. 1. The apparatus 830 may comprise aprocessing module 800, a location module 832, or a user interface 808.

The user interface 808 may be in communication with the processor 802,of the processing module 800, to provide output to the user and toreceive input. For example, the user interface may include a displayand, in some embodiments, may also include a keyboard, a mouse, ajoystick, a touch screen, touch areas, soft keys, a microphone, aspeaker, or other input/output mechanisms. The processor may compriseuser interface circuitry configured to control at least some functionsof one or more user interface elements such as a display and, in someembodiments, a speaker, ringer, microphone and/or the like. Theprocessor and/or user interface circuitry comprising the processor maybe configured to control one or more functions of one or more userinterface elements through computer program instructions (e.g., softwareand/or firmware) stored on a memory accessible to the processor (e.g.,memory 204, and/or the like).

The apparatus 830 may include a location module 832 that may, in turn,be in communication with the processor 802, of the processing module 800and configured to cause the processor to receive blink data from alocation tag associated with a first sensor, receive proximity and/orposition data generated based on communications between the first sensorand a second sensor, the proximity data including the second sensoridentifier, calculating the location tag location data based on theblink data, and determining a first sensor position calculation based onthe proximity and/or position data. The location module 832 may befurther configured to cause the processor 802 to assign a priorityvalues to the location data and the sensor position calculation data,and determine the highest priority location data or sensor positioncalculation data available. In an example embodiment the location module832 may cause the highest priority location data or sensor positioncalculation data to be displayed on a graphic user interface 808 orstored in a memory 804. In an example embodiment, the location module832 may be configured to cause the processor 802 to determine a sensorposition calculation data associated with a location tag based on theprevious location data associated with the location tag. In an exampleembodiment, the location module 832 may be configured to cause theprocessor 802 to validate the location data based on the calculatedlocation data and the determined sensor position calculation data. In anexample embodiment the location module 832 may be configured todetermine a message route based on the calculated location data of aplurality of location tags or determined position calculations of aplurality of sensors and transmit the message route in a monitored area.

FIGS. 9, 10, and 11 illustrate example flowcharts of the operationsperformed by an apparatus, such as apparatus 830 of FIG. 8c and sensor820 of FIG. 8b , in accordance with example embodiments of the presentinvention. It will be understood that each block of the flowcharts, andcombinations of blocks in the flowcharts, may be implemented by variousmeans, such as hardware, firmware, one or more processors, circuitryand/or other devices associated with execution of software including oneor more computer program instructions. For example, one or more of theprocedures described above may be embodied by computer programinstructions. In this regard, the computer program instructions whichembody the procedures described above may be stored by a memory 804 of aprocessing module 800 employing an embodiment of the present inventionand executed by a processor 802 in the processing module. As will beappreciated, any such computer program instructions may be loaded onto acomputer or other programmable apparatus (e.g., hardware) to produce amachine, such that the resulting computer or other programmableapparatus provides for implementation of the functions specified in theflowcharts' block(s). These computer program instructions may also bestored in a non-transitory computer-readable storage memory that maydirect a computer or other programmable apparatus to function in aparticular manner, such that the instructions stored in thecomputer-readable storage memory produce an article of manufacture, theexecution of which implements the function specified in the flowcharts'block(s). The computer program instructions may also be loaded onto acomputer or other programmable apparatus to cause a series of operationsto be performed on the computer or other programmable apparatus toproduce a computer-implemented process such that the instructions whichexecute on the computer or other programmable apparatus provideoperations for implementing the functions specified in the flowcharts'block(s). As such, the operations of FIGS. 9, 10, and 11 when executed,convert a computer or processing circuitry into a particular machineconfigured to perform an example embodiment of the present invention.Accordingly, the operations of FIGS. 9, 10, and 11 define an algorithmfor configuring a computer or processor, to perform an exampleembodiment. In some cases, a general purpose computer may be providedwith an instance of the processor which performs the algorithm of FIGS.9, 10, and 11 to transform the general purpose computer into aparticular machine configured to perform an example embodiment.

Accordingly, blocks of the flowchart support combinations of means forperforming the specified functions and combinations of operations forperforming the specified functions. It will also be understood that oneor more blocks of the flowcharts', and combinations of blocks in theflowchart, can be implemented by special purpose hardware-based computersystems which perform the specified functions, or combinations ofspecial purpose hardware and computer instructions.

In some example embodiments, certain ones of the operations herein maybe modified or further amplified as described below. Moreover, in someembodiments additional optional operations may also be included (someexamples of which are shown in dashed lines in FIGS. 9, 10, and 11). Itshould be appreciated that each of the modifications, optional additionsor amplifications described herein may be included with the operationsherein either alone or in combination with any others among the featuresdescribed herein.

Example Sensor Transmission Process

FIG. 9 illustrates a flowchart of an exemplary process for determining atransmission from a sensor. At 902, a sensor 820 may be providedincluding a transmission module 822 and a processing module 820. Thetransmission module 822 may be configured to cause the processor 802 todetermine receipt of a transmission reliability signal. Thecommunications circuitry 806 may receive transmission reliabilitysignals from exciters (e.g. exciters 112 as shown in FIG. 4) indicatingthe sensor 203 and associated tag 102 are within the monitored area orcrossing the boundary of a monitored area. Additionally oralternatively, the communication circuitry 806 may receive atransmission reliability signal from a transceiver (e.g. transceiver 107as shown in FIG. 4) indicating the associated tag 102 signal to receiver106 are not obstructed. In an instance in which the transmissionreliability is received by the processor 802, the processor 802 maycause the communication circuitry 806 transmit a signal configured tocause the tag to transmit blink data at 904 or cause the transmission oftag blink data 906 and transmit proximity or position data at 908. In aninstance in which the processor 802 determines the transmissionreliability signal has not been received, the processor may cause thecommunication circuitry to transmit a signal configured to terminateblink data transmission 909 and transmit proximity or position data 910,or terminate blink data transmission 911, transmit a distress signal912, and transmit proximity or position data 914.

At 904 and 906, the transmission module may be configured to cause theprocessor 802 to cause the transmission blink data. The processor 802may cause the communication circuitry 806 to transmit a signal to theassociated tag 102 configured to cause the tag to commence transmittingtag blink data based on the determination of receipt of the transmissionreliability signal at 902. The commence transmitting signal may be ashort range low frequency signal as discussed in FIG. 4 or through wiredcommunication in an instance in which the sensor and tag are housed in amonitoring unit, such as monitoring unit 510. The transmission of blinkdata is discussed in FIG. 1.

At 909 and 911, the transmission module may be configured to cause theprocessor 802 to cause the termination of blink data transmission. Theprocessor 802 may cause the communication circuitry 806 to transmit asignal to the associated tag 102 configured to cause the tag to commenceterminate transmitting tag blink data based on the determination of afailure to receive of the transmission reliability signal at 902. Theterminate transmitting signal may be a short range low frequency signalas discussed in FIG. 4 or through wired communication in an instance inwhich the sensor and tag are housed in a monitoring unit, such asmonitoring unit 510.

In an example embodiment, the processor 802 may cause the communicationscircuitry 806 to transmit a signal to the tag 102 configured to altertag blink rate based on the receipt of the transmission reliabilitysignal. For example the sensor 820 may cause the tag 102 to blink at 56Hz when within the monitored area or unobstructed and 1 Hz when outsideof the monitored area or obstructed.

At 908, 910, and 914, the transmission module 822 may be configured tocause the processor 802 to cause the communications circuitry 806 totransmit proximity or position data at 908. The communication circuitry806 may transmit proximity or position data by NFC, Wi-Fi, BLE, or thelike. The proximity or position data may be received by mesh nodes, suchas mesh nodes 203 b-e of FIG. 4 or a transceiver, such as transceiver107 of FIG. 4. Sensor proximity data may include the associated tag orsensor UID, proximity transmission radius, or other data indicative ofthe proximate location of a sensor. Sensor position data may include atriangulation position, such as GPS or ISO-2, or telemetry data. In anexample embodiment the sensor UID or associated tag UID is appended tothe proximity or position data for later use in determination of numberof transmissions or system diagnostics.

In an example embodiment, the transmission module 822 may be configuredto cause the processor 802 to cause the communication circuitry 806 totransmit via one or multiple location methods within a monitored areaand transmit on a different or single location method when outside ofthe monitored area based on the transmission reliability signal. Forexample, the communication circuitry 806 may transmit proximity andposition data at 908 within the monitored area. Outside of the monitoredarea the processor 802 may cause the communication circuitry 806 to onlytransmit proximity or position data at 910 or 914.

In an instance in which the processor 802 fails to receive thetransmission reliability signal, the transmission module 822 may assumethat the tag blink data transmissions would be obstructed, for example,by a pile up of players in football, a rugby scrum, or a player holdinganother player. The transmission module 822 may be configured to causethe processor 802 to cause the communication circuitry 806 to transmit adistress signal at 912. The distress signal may be received by meshnodes 203 b-e.

In an example embodiment, the transmission module 822 is configured tocause the processor 802 to cause in turn the communication circuitry 806to cause the transmission of blink data and transmit proximity and/orposition data without a determination of receipt of the transmissionreliability signal. For example, location systems using redundantlocation methods may have transmission modules 822 configured to causethe processor 802 to cause the communication circuitry 806 to transmitproximity and position data for validation of location and positioncalculations and/or as a secondary location/position determination.

Example Mesh Node Transmission Process

FIG. 10 illustrates a flowchart of an exemplary process for determininga transmission from a mesh node. The mesh node may be a sensor 820including a transmission module 822 and a processing module 800. Thetransmission module may be in communication with the processor 802 ofthe processor module 800. At 1002, the transmission module 822 may beconfigured to cause the processor 802 to receive from a communicationcircuitry 806, a first proximity or position data from an origin node,such as origin node 203 a of FIG. 4. The processor 802 may be configuredto receive the origin node 203 a proximity or position data over a meshnetwork protocol through NFC, Wi-Fi, BLE, or the like. The mesh node 820may continue the process at data path A, B, C, D, E, or F depending onthe sensor configuration. In data path A at 1004, the transmissionmodule 822 may be configured to cause the processor 802 to cause thecommunications circuitry 806 to transmit a signal configured to causethe transmission of tag blink data from the associated tag 102, asdescribed at 904 of FIG. 9, disregarding the received origin node 203 aproximity or position data. The mesh node 820 may not be configured totransmit origin node 203 a data or may have determined that transmissionof origin node data should not be performed in data path D, E, or F.

In data path B, the transmission module 822 may be configured to causethe processor 802 to cause the communications circuitry 806 to transmita signal configured to cause the transmission of blink data by a tagassociated with the mesh node 820 at 1006 as discussed at 904 of FIG. 9and transmit mesh node proximity or position data at 1008. Thecommunication circuitry may transmit the mesh node proximity of positiondata through the mesh network protocol through NFC, Wi-Fi, BLE, or thelike for receipt by a sensor transceiver 107 using mesh nodes 203 c-e.In an example embodiment, the mesh node 820 proximity and/or positiondata may be transmitted for receipt by a directional long rangetransceiver antenna, such as 107 a.

Origin node proximity data may include the origin node UID, proximitytransmission radius, or other data indicative of the proximate positionof an origin node. Origin node position data may include a triangulationposition, such as GPS or ISO-2, or telemetry data. In an exampleembodiment the mesh node UID is appended to the proximity or positiondata for later use in determination of number of transmissions or systemdiagnostics. In an example embodiment, the origin node proximity data isused to generate the mesh node proximity or position data by appendingthe associated tag or sensor UIDs of all tags/sensors including theorigin node for which proximity data was received in the mesh nodeproximity data. The mesh node 102 b may not be configured to transmitorigin node 203 a data or may have determined that transmission oforigin node data should not be performed in data path D, E, or F. Originnode position data may include a triangulation position, such as GPS orISO-2, or telemetry data.

In data path C, the transmission module 822 may be configured to causethe processor 802 to cause the communications circuitry 806 cause theassociated tag to transmit blink data at 1010 as discussed in 904 ofFIG. 9, transmit mesh node proximity or position data at 1012 asdiscussed at 1008, and transmit origin node proximity or position tagdata at 1014. The process may repeat at 1002 until the node and/ororigin node data reaches a transceiver 107.

At 1014, the transmission module 822 may be configured to cause theprocessor 802 to appended the mesh node 820 associated tag or sensor UIDin addition to the origin node associated tag or sensor UID to theproximity or position data for later use in determination of number oftransmissions or system diagnostics. Additionally, the mesh nodetag/sensor UIDs may be used for system analytics and diagnostics todetermine the route the message took through the mesh network. Theprocessor 802 may then cause the communication circuitry 806 to transmitthe origin node 203 a proximity or position data, in a mannersubstantially similar to the transmission of mesh node data at 1008.

In data path D may apply in an instance in which the origin nodeproximity or position data is transmitted through a mesh network, thetransmission module 822 may cause the processor 802 to limit thetransmission to prevent the message from being perpetually transmittedthroughout the monitored area. At 1016, the transmission module 822 maycause the processor 802 to determine if a message count has satisfied apredetermined threshold. The message count may include a transmissioncount such as 3, 4 or 5 transmissions; or a time count, such as 3, 2, or1 seconds. The number of transmissions may be determined by anincremental count in the message data, or by the number of tag UIDs thathave been appended to the message data. If the processor 802 determinesthe message count satisfies a pre-determined threshold, the transmissionmodule 822 may cause the processor 802 to transmit data as discussed indata path A or B. In an instance in which the processor 802 determinesthat the message count fails to satisfy the threshold, the processor maycause the communication circuitry 806, the transmit data as discussed indata path C, therefore sending the proximity and position data to thenext mesh node 203 b in the mesh network or to the transceiver 107.

For example, if the message count is 4 transmissions and the mesh node820 receives origin node 203 a proximity or position data with anincremental count of 3 or 3 tag/sensor UIDs, the mesh node may determinethe message count is not satisfied and continue the process at data pathC. At data path C, processor 802 of the mesh node 820 may cause thecommunication circuitry 806 to transmit a signal configured to cause thetransmission of blink data by the associated tag 102, transmit mesh node820 proximity or position data, and transmit origin node 203 a proximityor position data. In an instance in which the incremental count is 4 or4 tag/sensor UIDs present, the processor 802 may determine the messagecount has been satisfied and disregard the origin node data in data pathA or B. The processor 802 may cause the communication circuitry totransmit a signal configured to cause the transmission of the blink dataof the associated tag 102 in data path A, or transmit a signalconfigured to cause the transmission of blink data from the associatedtag 102 and transmit the mesh tag 820 proximity or position data in datapath B.

Data path E may be applied in an instance in which the sensor proximityor position data is being transmitted through a mesh network, thereceiver hub 108 or receiver processing and distribution system 110 maydetermine the best route (e.g. smallest number of transmissions to reacha transceiver 107) for the message and transmit the route to the sensorsin the monitored area. In data path E, the transmission module 822 maycause the processor 802 to receive a message route from communicationcircuitry 806 at 1018. Communication circuitry 806 may receive themessage route from transceivers 107. At 1020, the transmission module822 may cause the processor 802 to determine if the mesh node 820 isdesignated in the received message route. If the processor 802determines the mesh node 102 b is not designated in the message route,the processor 802 may cause the communication circuitry 806 to cause thetransmission of blink data from the associated tag 102 or cause thetransmission of blink data from the associated tag 102 and transmit meshnode proximity or position data as discussed in data path A or B. If theprocessor 802 determines that mesh node 820 is designated in the messageroute, the processor 802 may cause the communication circuitry 806 tocause the transmission of blink data from the associated tag 102 andtransmit mesh node 820 and origin node 203 a position or proximity dataas discussed in data path C.

Data path F may be applied in an instance in which the origin node isconfigured to send a distress signal in response to failing to receive atransmission reliability signal as discussed in FIG. 9. The distresssignal may be indicative of a tag or sensor data transmission beingobstructed. At 1022, the transmission module 822 may be configured tocause the processor 802 to determine receipt of a distress signal fromthe communication circuitry 806. Communication circuitry 806 may receivethe distress signal from an origin node 203 a. In an instance in whichthe processor 802 fails to receive an indication of receipt of adistress signal from an origin node 203 a, the processor 802 may assumethe tag 102 or sensor data is not obstructed and cause transmission ofdata as discussed in data path A or B. In an instance in which theprocessor 802 does receive an indication of the receipt of a distresssignal from an origin node 203 a, the processor may determine that thetag and/or the origin node is obstructed and continue data processing asdiscussed in data path D or E, or transmit data as discussed in datapath C.

Example Over-Determined Location Determination Process

FIG. 11 illustrates an exemplary process for determining anover-determined participant location. An apparatus 830 such as areceiver hub 108 or receiver processing and distribution system 110 mayinclude a location module 832, a processing module 800, and a userinterface 808. The location module 832 may be configured to cause theprocessor 802 to generate a location hierarchy by assigning priorityvalues to each location and position method the location system mayutilize. For example, UWB location data may be assigned a priority valueof 1; proximity position calculation based on a UWB location may have apriority value of 2; triangulation position calculation such as GPSbackhauled over Wi-Fi or ISO-2 may have a priority value of 3; ISO-2,Wi-Fi RSSI, and proximity position based on triangulation positioncalculation may have a priority value of 4; where 1 represents thehighest priority value and 4 the lowest priority value.

In an example embodiment, the processor may generate locationhierarchies for two or more monitored areas. For example, a firstmonitored area may the race track or course, with a location hierarchyincluding GPS backhauled over Wi-Fi or ISO-2 with a priority value of 1,UWB location data priority value of 2, Wi-Fi RSSI, and proximityposition based on triangulation position calculation may have a priorityvalue of 3. A second monitored area may be the pit, or transmissionpoint of a race with a location hierarchy including UWB location datawith a priority value of 1; triangulation position calculation such asGPS backhauled over Wi-Fi or ISO-2 with a priority value of 3; ISO-2,Wi-Fi RSSI, and proximity position based on triangulation positioncalculation may have a priority value of 3.

At 1102, the location module 832 may be configured to cause theprocessor 802 to receive blink data from communications circuitry 806.The communication circuitry 806 may receive blink data from thereceivers 106. At 1108, the location module 832 may be configured tocause the processor 802 to calculate location data based on the receivedblink data as discussed in FIG. 1.

At 1104, the location module 832 may be configured to cause a processor802 to receive mesh node 203 b proximity or position data from thecommunications circuitry 806. The communication circuitry 806 mayreceive the sensor 820 or mesh node 203 b proximity or position datafrom the transceiver 107. The proximity data may include dataidentifying one or more mesh nodes 203 b in proximity to the specifiedorigin node 203 a, such as the origin node and mesh node UIDs or theirassociated tag UIDs. Additionally the proximity data may include dataindicative of a proximity radius, such as a Wi-Fi RSSI. The positiondata may include telemetry data or a triangulated position data, such asDGPS or ISO-2.

The transceiver 107 may receive sensor 820 or mesh node 203 b proximityor position data through a mesh network protocol through mesh nodes 203b-e transmitting in NFC, BLE, or Wi-Fi. Alternatively, the transceiver107 a may direct backhaul proximity or position data from a sensor 820or mesh node 203 b using a directional long range transceiver antenna107 a. Origin node 203 a proximity or position data may be received in asubstantially similar manner at 1106.

At 1110, the location module 832 may be configured to cause theprocessor 802 to determine sensor 820 or mesh node 203 b proximityposition data. Each sensor may have a predetermined range fortransmission of the proximity data, limiting the receipt of theproximity data to a specified radius. For example, the range may be 10ft, 4 ft, 2 ft, or any other radial distance value. The processor 802may calculate location data and a proximity radius for each tag forwhich proximity data was received from an associated sensor 203, asillustrated in FIG. 5 a.

At 1120, the location module 832 may be configured to cause theprocessor 802 to determine the sensor 820 or participant 402 positioncalculation based on the sensor proximity data. The processor 802 maydetermine a sensor 820 position calculation as the position or area inwhich the sensor proximity radii intersect, as depicted in FIG. 5 a.

In an example embodiment the processor may weight located sensorpositions based on the Wi-Fi RSSI and/or determine a transmission rangebased on the Wi-Fi RSSI. The processor 802 may determine the proximityposition based on the determined transmission range radius intersectionsand/or weighting the area or position based on the RSSI for eachproximate sensor 203.

At 1114, the location module 832 may be configured to cause theprocessor 802 to determine an origin node 203 a proximity position datain a manner substantially similar to 1110. The processor 802 maydetermine the origin node 203 a position calculation based on proximityposition data in a manner substantially similar to 1120.

At 1112, the location module 832 may be configured cause the processor802 to determine sensor 820 or mesh node 203 b position data. Theprocessor 802 may compile triangulation position data or telemetry datareceived from various sensors 203. The processor 802 may be configuredto determine the origin node 203 a position data in a substantiallysimilar manner at 1116.

The location module 832 may be configured to cause the processor 802 todetermine the origin node 203 a position calculation based on the sensorposition data at 1120 as discussed in FIG. 3E/F. The processor 802 maydetermine the sensor position calculation based on the position datadetermined at 1112 or 1116, by associating the triangulation position tothe sensor 203, or calculating the sensor position using the telemetrydata as discussed in FIG. 3E/F.

At 1118, the location module 832 may be configured to cause theprocessor 802 to validate location data. The processor 802 may validatelocation data by comparing determined proximity sensor positioncalculation data to the location data as shown in FIG. 5b . If thecalculated location data is within a predetermined threshold of accuracyradius to the proximity sensor position calculation data, the processor802 may determine the location data is validated. In an instance inwhich the location data fails to satisfy the predetermined threshold ofaccuracy, falling outside of the sensor proximity position calculationaccuracy radii, the processor 802 may determine the location data isinvalid and is considered missed. A missed location data may beconsidered unavailable for determination of highest priority locationdata or position calculation available. 1122 and is not used for displayor analytics, but may be stored for later system diagnostics.

In an example embodiment, the location module 832 may be configuredcause the processor 802 to validate location data by comparing thelocation data to the determined sensor position calculations, as shownin FIG. 5b . In an instance in which, the calculated location data fallswithin a predetermined threshold of accuracy radius of the sensorposition calculation data, the processor 802 may determine the locationdata is valid. In an instance in which the location data falls outsidethe predetermined sensor position calculation data radius, the processor802 may determine the location data is invalid and considered missed.

In an example embodiment, the location module 832 may be configured tocause the processor 802 to validate location data by comparing thecurrent location data to the previously calculated location data.Previously calculated location data may include the last 2, 5, 10, 20 oranother number of location data that were calculated prior to thelocation data that is being validated. In an instance in which thechange in location data satisfies a predetermined threshold such as 2ft, 5 ft, 20 ft, 30 ft, 100 ft, or any other distance value, theprocessor 802 may determine that the tag 102 could not travel thatdistance between blinks and the location data is invalid and consideredmissed. For example, if the difference in location data is 35 ft and thepredetermined threshold is 25 ft, the processor may determine that thelocation data is invalid. A missed location data is consideredunavailable and may not be used for further determinations. In aninstance in which the change in location data fails to satisfy thepredetermined threshold, the processor 802 may determine the locationdata is valid and may be available and used for further determinations.

At 1122, the location module may be configured to cause the processor802 to determine a message route. In an instance in which an origin node203 a proximity or position data or the blink data for a tag 102associated with an origin node has not been received, the processor 802may determine a message route for the origin data through the meshnetwork. The processor 802 may use the last location data and positioncalculation of the participant 402 a and mesh nodes 203 b-e to determinethe shortest route to the transceiver 107, e.g. the smallest number oftransmissions. The processor 802 may determine and designate mesh nodesby sensor UID, associated tag UID, or other identification. Theprocessor 802 may generate a message route comprising the designatedmesh node identifiers.

At 1123, the location module may cause the processor 802 to cause thecommunication circuitry 806 to transmit the message route. Thecommunication circuitry 806 may transmit the message route to thetransceiver 107 for transmission to the sensors 820 within the monitoredarea.

At 1124, the location module 832 may be configured to cause theprocessor 802 to determine highest priority location or sensor positioncalculation data available, or over-determined location, for eachparticipant 402. The processor 802 may determine the available locationdata and sensor position calculation data for each participant 402. Theprocessor 802 may select the location data or sensor positioncalculation data based on the location hierarchy with the highestpriority value assigned at 1101 from the available location and sensorposition calculation data for the participant 402. For example, if UWBlocation data-priority 1 and GPS sensor position calculation datapriority-2 are available the processor 802 may select the UWB locationdata. In an instance in which the processor 802 determines that UWBproximity position calculation-priority 2 and Wi-Fi positioncalculation-priority 3 are available, UWB proximity position calculationmay be selected. In an instance in which two or more location/positionmethods are available and have the same priority value the determinedposition calculation may be an average of the selected location orsensor position calculation data.

In an example embodiments in which the monitored area includes two ormore areas each having a location hierarchy, the processor 1202 maydetermine the monitored area associated with the location data or sensorposition calculation data. The processor 1202 may determine the highestpriority location data or sensor position calculation data, orover-determined location based on the location hierarchy of themonitored area associated with the location data and sensor positioncalculation data. For example, in which the location data or sensorposition calculation data is associated with the first monitored areaand location hierarchy, if the GPS sensor position calculationdata-priority 1 and UWB location data priority-2 are available theprocessor 802 may select the GPS sensor position calculation data as theover-determined location. In an instance in which the location data orposition calculation data is associated with a second monitored area andlocation hierarchy if UWB location data-priority 1 and GPS sensorposition calculation data priority-2 are available the processor 802 mayselect the UWB location data as the over-determined location.

At 1125, the location module 832 may be configured to cause theprocessor 802 to cause at least the highest priority location or sensorposition calculation data, or the over-determined location to be storedin a memory 804. The processor 802 may also store any other locationdata, or sensor position calculation data, position data, or proximitydata in a memory 804 for later analytics or system diagnostics. Forexample, if an UWB location data-priority 1, an UWB proximity positioncalculation-priority 2 and a GPS position calculation-priority 3 areavailable; the processor may cause only the UWB location data to bestored, or store the UWB location data and UWB proximity sensor positioncalculation data, or store the UWB location, the UWB proximity sensorposition calculation data and the GPS sensor position calculation data.

At 1126, location module 832 may cause the processor 802 to cause thehighest priority of location or sensor position calculation data, orover-determined location to be displayed on a user interface 808. Forexample, in an instance where UWB location data is the highest priority,the processor 802 may cause the UWB location data to be displayed. In aninstance when UWB location data is unavailable, but UWB proximity sensorposition calculation data is available, the processor 802 may cause theuser interface 808 to display the UWB proximity calculation data. In anexample embodiment, the highest priority location or position isdisplayed and lower priority location or positions may be overlaidsimilar to the depiction of the radial accuracy thresholds shown in FIG.5 b.

In some embodiments, certain ones of the operations above may bemodified or further amplified as described below. Moreover, in someembodiments additional optional operations may also be included. Itshould be appreciated that each of the modifications, optional additionsor amplifications below may be included with the operations above eitheralone or in combination with any others among the features describedherein.

Many modifications and other embodiments of the inventions set forthherein will come to mind to one skilled in the art to which theseinventions pertain having the benefit of the teachings presented in theforegoing descriptions and the associated drawings. Therefore, it is tobe understood that the inventions are not to be limited to the specificembodiments disclosed and that modifications and other embodiments areintended to be included within the scope of the appended claims.Moreover, although the foregoing descriptions and the associateddrawings describe example embodiments in the context of certain examplecombinations of elements and/or functions, it should be appreciated thatdifferent combinations of elements and/or functions may be provided byalternative embodiments without departing from the scope of the appendedclaims. In this regard, for example, different combinations of elementsand/or functions than those explicitly described above are alsocontemplated as may be set forth in some of the appended claims.Although specific terms are employed herein, they are used in a genericand descriptive sense only and not for purposes of limitation.

That which is claimed is:
 1. A method of tracking a participant movinginto and outside of a monitored area, the method comprising: receivinglocation data calculated based on blink data transmitted by a locationtag associated with the participant; receiving sensor positioncalculation data calculated based on sensor data transmitted by a sensorassociated with the participant; determining, by a processor, a locationof the location tag based on the location data; selecting the locationfor the participant when the location tag is in the monitored area;determining, by the processor, a position of the sensor based on thesensor position calculation data; and selecting the position for theparticipant when the sensor is outside the monitored area.
 2. The methodof claim 1, wherein the location tag is configured to transmit blinkdata at a first blink rate when receiving a transmission reliabilitysignal and to transmit blink data at a second blink rate, which is lessthan the first blink rate, when not receiving a transmission reliabilitysignal.
 3. The method of claim 1 further comprising: receiving, by atleast one of the location tag or the sensor, a transmission reliabilitysignal transmitted from one or more exciters positioned proximate themonitored area; and determining, by the processor, when the participantis in the monitored area and outside the monitored area based on thetransmission reliability signal.
 4. The method of claim 1, furthercomprising determining, by the processor, an over-determined locationwhen the participant is in the monitored area.
 5. The method of claim 1,further comprising, not determining the location of the location tagbased on the location data when the participant is outside of themonitored area.
 6. An apparatus comprising at least one processor and atleast one memory including computer program code, the at least onememory and computer program code configured to, with the processor,cause the apparatus to: receive location data calculated based on blinkdata transmitted by a location tag associated with a participant;receive sensor position calculation data calculated based on sensor datatransmitted by a sensor associated with the participant; determine alocation of the location tag based on the location data; selecting thelocation for the participant when the location tag is in a monitoredarea; determine a position of the sensor based on the sensor positioncalculation data; and selecting the position for the participant whenthe sensor is outside the monitored area.
 7. The apparatus of claim 6,wherein the location tag is configured to transmit blink data at a firstblink rate when receiving a transmission reliability signal within themonitored area and to transmit blink data at a second blink rate, whichis less than the first blink rate, when not receiving a transmissionreliability signal outside the monitored area.
 8. The apparatus of claim6 wherein: at least one of the location tag or the sensor is configuredto receive a transmission reliability signal transmitted from one ormore exciters positioned proximate the monitored area; and the at leastone memory and computer program code is configured to, with theprocessor, cause the apparatus to determine when the participant is inthe monitored area and outside the monitored area based on thetransmission reliability signal.
 9. The apparatus of claim 6, the atleast one memory and computer program code configured to, with theprocessor, cause the apparatus to determine an over-determined locationwhen the participant is in the monitored area.
 10. The apparatus ofclaim 6, the at least one memory and computer program code configured tonot determine the location of the location tag based on the locationdata when the participant is outside of the monitored area.
 11. Alocation system configured to track a participant moving into andoutside of a monitored area, the location system comprising: a locationtag configured to transmit blink data, wherein the location tag isassociated with the participant; a sensor configured to transmit sensordata, wherein the sensor is associated with the participant; a pluralityof receivers configured to receive the blink data and to determinelocation data based on the blink data; a receiver hub configured to:receive the location data; receive sensor position calculation datacalculated based on the sensor data; determine a location of thelocation tag based on the location data; select the location data forthe participant when the participant is in the monitored area; determinea position of the sensor based on the sensor position calculation data;and select the position for the participant when the participant isoutside the monitored area.
 12. The location system of claim 11, whereinthe location tag is configured to transmit blink data at a first blinkrate when receiving a transmission reliability signal within themonitored area and to transmit blink data at a second blink rate, whichis less than the first blink rate, when not receiving a transmissionreliability signal outside the monitored area.
 13. The location systemof claim 11, at least one of the location tag or sensor to receive atransmission reliability signal transmitted from one or more exciterspositioned proximate the monitored area, the receiver hub configured todetermine when the participant is in the monitored area and outside themonitored area based on the transmission reliability signal.
 14. Thelocation system of claim 11, wherein the receiver hub is configured todetermine an over-determined location when the participant is in themonitored area.
 15. The location system of claim 11, wherein thereceiver hub is configured to not determine the location of the locationtag based on the location data when the participant is outside of themonitored area.